AudioCircle

Industry Circles => Tortuga Audio => Topic started by: tortugaranger on 9 Jun 2014, 12:17 pm

Title: Firmware Updates - V2/2.1
Post by: tortugaranger on 9 Jun 2014, 12:17 pm
Our software update/download page is now live on our website for the new ldr3x.V2 preamp controller board.  :thumb:

We encourage owners of the V2 board to update their software to the latest version. This is especially important for those with the earliest versions 1.0.0 through 1.0.3 of the software since numerous bugs etc. have been taken care of since initial release. We anticipate that updates will slow down substantially over the next few weeks as the product matures. Announcements of new releases will be posted on this forum.

Please note that owners of dual V2 boards used in balanced audio configurations need to upload software updates separately into each board.

The software update/download page can be found here under the Support menu: http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)

More info on the LDR3x.V2 here:  http://www.tortugaaudio.com/product/ldr3x-passive-preamp-controller-version-2/ (http://www.tortugaaudio.com/product/ldr3x-passive-preamp-controller-version-2/)

The pic below shows the micro-b usb port on the V2 board that's used to upload software revisions.
(http://www.tortugaaudio.com/images/ldr3x.v2.usb_.jpg)

Title: Re: Firmware Updates
Post by: tortugaranger on 9 Jun 2014, 08:49 pm
As of 6.9.14 we released version 1.0.5 and later the same day released version 1.0.6
Details and downloads here: http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)
Title: Re: Firmware Updates
Post by: tortugaranger on 22 Jun 2014, 02:41 pm
Update #1 on this - All V2 customers with the original issue Rev 1 Bootloader will be receiving an updated chip.
_________________________________
2-3 V2 customers have reported a buzzing sound from the V2 when it first powers up. After getting some feedback and doing some diagnostic work I believe I've identified the cause of this and a solution. Read on.

Can't Buzz Here -  Try is we might, we can't get any V2 board to buzz in our shop. We test each individual board before shipping them out including running music through them and numerous functional checks. No board has ever buzzed for us although I wish one had so we could've resolved this early on. Can't solve problems you don't know you have. Also, apparently only a very few of the V2 boards shipped so far exhibit this buzzing behavior.

About The Bootloader - The V2 has 2 separate pieces of software - a bootloader and the main V2 app. The sole purpose of the bootloader is to allow software updates to the main V2 app via the USB port. Each time power is applied to the V2 board, the bootloader runs for 5 seconds. If it doesn't make a valid USB connection within those 5 seconds, it gives up and hands over control of the V2 to the main V2 app. Only the main V2 app can be updated via the USB port. To change the bootloader requires that the microcontroller chip be replaced with another chip with an updated bootloader.

What's Buzzing & Why? - The buzzing sound is the rapid cycling of the 4 relays located on the auto calibration piggyback board which is located on the underside of the V2. The autocal relays are energized via the AutoCal command signal from the V2 microcontroller. The AutoCal command signal causes the Q1 (mosfet/transistor) switch on the autocal board to "turn on" which energizes the relays by connecting them to ground. Normally, this works fine and is controlled by the main V2 app. The buzz problem occurs during the 5 second window during which the bootloader has control. Rev 1 (the original rev) of the bootloader doesn't configure or control any of the V2 microcontroller outputs including the output to Q1. As a result, Q1 can become electrically "confused" since it's not getting a clear command to either turn on or to turn off. Apparently there's enough variability in the behavior of Q1s that  only a small subset of the ones we've used get sufficiently confused to cycle on/off causing the buzz.

Is The Buzzing Harmful? - A few seconds of cycling the relays on/off as power is applied won't hurt the V2 board. To be clear, this doesn't happen when the V2 is turned on/off, only upon 12 VDC electrical power being applied to the board. However, you are strongly advised to have your amp turned off when applying power to the V2 or removing power from the V2.  

The Fix Is In! - The fix is an updated bootloader (Rev 2) which makes sure the AutoCal command to the relays is live and turned on the instant the V2 powers up. Enabling AutoCal disconnects the V2 from its audio signal inputs/outputs which is a good idea as the V2 powers up and initializes. Getting a Rev 2 bootloader requires the microcontroller to be replaced. If your unit exhibits buzzing and/or you wish to get the updated bootloader please let us know and we'll ship you a new chip. All V2 units shipped on or after 6.20.14 already have the Rev 2 bootloader.

Any questions on this don't hesitate to post here, send a PM or email (morten@tortugaaudio.com).
Title: Re: Firmware Updates
Post by: tortugaranger on 22 Jun 2014, 08:21 pm
See update to prior post below.
Title: Re: Firmware Updates
Post by: tortugaranger on 24 Jun 2014, 05:11 pm
As of 6.20.14 we've released version 1.0.7

The biggest change is in the timing/duration of auto-calibration cycles which now have a 5 minute pause between each cycle. With this release AutoCal doesn't commence until 5 minutes after the V2 is turned off. There are certain amps (the Job 225 in particular) that aren't happy (may hum)  when the audio I/O gets disconnected during AutoCal. The 5 minute delay provides ample time to shut down your amp after shutting down the V2.

I would encourage users of the V2 to utilize the 12 V Trigger Out feature of the V2 which can provide a start/shutdown signal to external sources/amps etc. that have 12 volt trigger feature so when the V2 is turned on/off those items are automatically turn on/off as well.

Details and software downloads can be found here: http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)
Title: Re: Firmware Updates
Post by: tortugaranger on 26 Jun 2014, 06:40 pm
Posted software version 1.0.8 - 6.26.14

Fix: Removed a bug that, when the unit was turned off, caused the Status LED to light up when the Left or Right (Input Change) button was pressed on the Apple Remote.
New: Pressing the Center/Enter button on the Apple Remote will start/stop (toggle) AutoCal. If it's in between cycles, an AutoCal cycle will commence. Likewise, if AutoCal is already running, it will shut off AutoCal. Please note that this does not enable/disable AutoCal generally, it just toggles a single AutoCal cycle. This was a hidden feature to aide in testing/diagnostics but we decided to release and document it.

The V2 Software Download page can be found here: http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)
Title: Re: Firmware Updates
Post by: tortugaranger on 30 Jun 2014, 12:55 pm
Given the ongoing discussion regarding Auto Calibration, I've split those posts off into its own V2 Auto Calibration topic located here:  http://www.audiocircle.com/index.php?topic=127046.0 (http://www.audiocircle.com/index.php?topic=127046.0)
This V2 Software Updates topic will continue to be used to post software update announcements and as a starting point for questions/suggestions regarding software changes.

Thanks
Morten
Title: Re: Firmware Updates
Post by: tortugaranger on 30 Jun 2014, 04:41 pm
Posted software update 1.0.9 on 6.30.14 which is available here:  http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)

Fix: This update corrects the IR Remote ID recognition and pairing so that the user can correctly:

a) Pair the V2 with either or both the Apple Remote and/or the legacy Tortuga Audio Remote; and
b) Pair the V2 with only the Apple Remote or only the Tortuga Audio Remote; and,
c) Change the ID of the Apple Remote and re-pair (teach) the V2 the new Apple Remote ID.

Please note the following specifics:

Title: Re: Firmware Updates
Post by: tortugaranger on 15 Jul 2014, 10:29 pm
Here are the last 3 V2 software updates. Update 1.1.0 is significant. Latest cummulative build (1.1.2) available here: http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)

1.1.2 - 7.15.14 - This update is primarily relevant to those who only use an Encoder and not the Apple Remote to control the V2

New: Can now toggle AutoCal on/off with Encoder via quarter/half turn to right
New: Status LED now flashes briefly every 2-3 seconds when AutoCal is active
New: Left display module in dual display system now shows which LDR is in AutoCal (1-4)

1.1.1 - 7.7.14

Fix: Removed blinking of numerical display when changing volume. Status LED still blinks as before. Bug was introduced in 1.1.0.

1.1.0 - 7.6.14

Change:  With the release of Rev 1.1.0, we have made the following changes to how auto calibration is run:
* AutoCal now runs only when manually initiated by the user while the V2 is turned off but still connected to power. We do recommend that the V2 be powered but turned off when not in use.
* AutoCal is started by pressing the Enter/Center button on the remote which disconnects the V2 from the audio input and output.
* Once AutoCal is initiated, it runs through one full cycle of LDR calibration in the following LDR sequence: right-series, right-shunt, left-series, left-shunt.
* Upon completing a full cycle, AutoCal shuts off and the V2 is reconnected to the audio input and output.
* While AutoCal is running it can be shut off prior to completing a full calibration cycle by pressing the Enter/Center button again on the remote. The V2 may not react immediately to this AutoCal shut down command and it may have to be repeated. We recommend you not interrupt the V2 during a calibration cycle once initiated. A full calibration cycle typically takes around 10 minutes.
* While AutoCal is running, you can cause AutoCal to interrupt calibration on the current LDR and switch to the next LDR in the cycle by pressing the Right button on the remote. If you switch through all 4 LDRs then AutoCal will shut down thinking its completed a full calibration cycle. This feature is provided as a diagnostic tool only. We highly recommend that you not interrupt AutoCal while its running.
* While AutoCal is running, the V2 will display each volume step (1-70)  in the process for each LDR. Thus it will go through 70 calibration steps four times in a row over the course of a full calibration cycle.
* When AutoCal is complete or shut down deliberately, the display will also shut off.
* We recommend you turn your amp off before initiating an AutoCal cycle. Physically disconnecting your cables from the V2 isn't necessary.
* We recommend you run AutoCal monthly but this is simply a recommendation and not a requirement.
Title: Re: Firmware Updates
Post by: tortugaranger on 2 Aug 2014, 01:19 pm
1.1.4 - 7.29.14 - A couple of minor adds/tweaks plus a fix for those with balanced V2s.  Latest cummulative build (1.1.2) available here: http://www.tortugaaudio.com/downloads/

* New: Displays 3 digit software build  number when power is applied. Since the display is only 2 digit, each of the 3 software build digits are shown individually one at a time.
* Tweak: Minors mods to left/right channel info displays for those using dual displays.
* Fix: Slave board was not receiving AutoCal start/stop or Next (skip) command signals. This fix is only relevant to those using V2's in balanced configuration. This was a bug introduced with update 1.1.0.
Title: Re: Firmware Updates
Post by: tortugaranger on 5 Aug 2014, 01:56 pm
1.1.5 - 8.5.14   This update only relevant to those using V2's in balanced audio configuration. http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)

* Change: Improved robustness of serial communications of volume data from Master-to-Slave in balanced systems.
* Fix: Removed ability of Slave to sometimes ramp volume back up to set  point by itself after receiving an Input Change command from the Master.
Title: Re: Firmware Updates
Post by: tortugaranger on 19 Aug 2014, 06:22 pm
We're now up to rev 1.1.8 of the V2 firmware. At least one person who was using earlier 1.1.3 reported a problem with intermittent non-response to remote commands. We encourage updating to the latest version which should be the most stable and reliable.

1.1.8 – 8.18.14

Fix: Removed unused timer2 code from interrupt handling routine. Was possibly interfering with remote.
Change:  Changed balance adjust limit from +/-10 to +/-9 to work within limitations of display
Fix: Removed adding +1 to left bias upon entering Bal Adjust Mode – bug from 1.1.7

1.1.7 – 8.15.14

Tweak: Cleaned up how left/right channel balance adjustment was handled

1.1.6 – 8.12.14

Fix: Corrected display info during AutoCal
Tweak: Display now shows all 0′s as soon as unit is turned on – removed prior delay.
Title: Re: Firmware Updates
Post by: tortugaranger on 4 Dec 2014, 02:37 pm
As I've mentioned in some recent posts, I'm planning on introducing some new features to the V2/V2.1 software. I'm looking for a wishlist/input from current/future owners on what you'd like to see added, hanged, removed.

Here is the list so far:

1) New feature: User selectable input impedance settings. Proposed settings starting at 5k, then 10k, 20k etc. up to 100k. Once you pick a setting, you'll need to rerun auto-cal for the new setting to become active. The results of each setting will be stored in memory so you'll be able to switch multiple settings on the fly to determine which sounds better in your rig.

2) Change: Turn off display. Some customers would like to turn off the display while unit is on. Will probably made this as simple as pressing any key on the remote to toggle display off/on.  To avoid confusion, if the display is off but the unit is on, pressing any button on the remote,  or turning the encoder knob, will first turn display back on before responding to any subsequent command. For example, if the display is blanked while unit is on and you press the power on/off button (Menu), the display will turn back on. You'll need to press power on/off a second time to actually turn the unit off.
Title: Re: Firmware Updates
Post by: Shakeydeal on 4 Dec 2014, 04:03 pm
Will these changes be available to current users by download to the USB port?

Shakey
Title: Re: Firmware Updates
Post by: tortugaranger on 4 Dec 2014, 04:04 pm
Will these changes be available to current users by download to the USB port?

Absolutely!
Title: Re: Firmware Updates
Post by: glynnw on 4 Dec 2014, 04:35 pm
Mono?
Title: Re: Firmware Updates
Post by: tortugaranger on 4 Dec 2014, 04:39 pm
Mono?

Care to elaborate on that....man of few words?
Title: Re: Firmware Updates
Post by: sfox7076 on 4 Dec 2014, 04:48 pm
How about programable volume start settings for the unit for each input. 
Title: Re: Firmware Updates
Post by: tortugaranger on 4 Dec 2014, 05:01 pm
How about programable volume start settings for the unit for each input.

The V2 kind of already has this feature. Each input remembers the last volume setting it was at when it was on. When you switch back to that input, it resumes at that same volume setting. A resume setting vs. a fixed preset setting.

One "feature" I've gotten push back on is that when inputs are switched,  the max resume volume setting will never be greater than 35 regardless of the prior setting that input was at. This is to prevent someone who uses the V2 in home theater bypass mode (with vol set at max-70) from switching to another input with volume set at max and possibly blowing out their speakers. I've been asked to either delete this limit, raise it higher, or allow user to set the limit value. I won't delete it altogether but open to considering other 2 options.
Title: Re: Firmware Updates
Post by: 33na3rd on 4 Dec 2014, 07:29 pm
A second on mono.

It's a vinyl thing!

Mono LP's do sound better when played in mono, even with a stereo cartridge.

The vast majority of phono units lack a mono switch. Some folks resort to a double Y adapter to get around this. You can imagine what those extra connectors from the double Y method do to the signal from the phono unit.

I'm considering adding a mono switch for one of my inputs on a future build to get around this.
Title: Re: Firmware Updates
Post by: tortugaranger on 4 Dec 2014, 09:20 pm
A second on mono.
It's a vinyl thing!
Mono LP's do sound better when played in mono, even with a stereo cartridge.
The vast majority of phono units lack a mono switch. Some folks resort to a double Y adapter to get around this. You can imagine what those extra connectors from the double Y method do to the signal from the phono unit.
I'm considering adding a mono switch for one of my inputs on a future build to get around this.

Ah yes, a mono switch. That requires connecting the right and left channel signals together and to do so would require a relay and there's no relay for that built into any of the Tortuga boards. The V2.1 board does have 2 extra 5 volt outputs which can be controlled via software and either output could be used to trigger an external mono relay.
Title: Re: Firmware Updates
Post by: robertopisa on 5 Dec 2014, 02:11 pm
Great idea Morten. As the impedance doubles for the balanced version, what if you drop 100k (who is using it?) in favour of 1K and 2.5K?
Actually, the range could be 1K, 2.5K, 5K, 10K, 15K, 20K, 30K, 40K, 50K. I do not think that over 50K is really useful.

Thanks
Roberto


1) New feature: User selectable input impedance settings. Proposed settings starting at 5k, then 10k, 20k etc. up to 100k. Once you pick a setting, you'll need to rerun auto-cal for the new setting to become active. The results of each setting will be stored in memory so you'll be able to switch multiple settings on the fly to determine which sounds better in your rig.
Title: Re: Firmware Updates
Post by: tortugaranger on 2 Mar 2015, 03:56 pm
After a ton (perhaps a few tons) of work, we are pleased to finally release the latest version of our LDR preamp controller firware that was developed as part of the V2.1 version of the LDR3x Preamp Controller Board.

This Rev 2.1.x firmware now includes both adjustable impedance as well as a greatly improved auto-cal algorithm. You can read more about it via this article: http://www.tortugaaudio.com/ldr-passive-preamps-with-adjustable-impedance/ (http://www.tortugaaudio.com/ldr-passive-preamps-with-adjustable-impedance/)

For convenience I've quoted the essential top lines below.

We've been shipping versions of this new firmware with our products starting back in January but we didn't want to formally release it and make it available to existing V2/preamp customers until such time as we felt it had a chance to mature.

Best,
Morten  :thumb:

Quote
March 1, 2015 - Tortuga Audio has released a major firmware update for its LDR Passive Preamp product line allowing the user to change the input impedance of their LDR passive preamp. This firmware update also includes an upgraded auto-calibration algorithm resulting in improved sound stage and stereo imaging.

The Adjustable Impedance feature allows the user to set up 5 different impedance settings, each between 1k and 99k, with setting #1 currently set up at 20k by default.

All Tortuga Audio preamp products shipped starting January 1, 2015 include some version of the updated 2.1.x firmware. This firmware update is also available to all existing owners of the V2 and V2.1 versions of the LDR3x passive preamp controller board as well as all passive preamp products equipped with a USB socket. Version 2.1.7 is considered the most complete, stable and reliable version as of this edit. Owners are encourage to upgrade to this version.

The latest firmware file plus the required PC compatible bootloader program (not available yet for MACs) can be downloaded from here.  Detailed instructions can be found there as well. The specific remote command sequences needed to adjust impedance can be found here in our online documentation.
Title: Re: Firmware Updates
Post by: Tomy2Tone on 2 Mar 2015, 05:20 pm
Sweet!

I just placed an order for your finished LDR3v2 pre and look forward to what it can do! I have a Job 225 thats currently in the trading post here but for fun I put in back in the chain over the weekend to see how it could handle my new speakers and it sounds pretty good. I'm considering getting the Job 250 monoblocks with a little more power but has the same high gain as the 225 and from everything I've read is a great match with your passive pre.
Title: Re: Firmware Updates
Post by: tortugaranger on 2 Mar 2015, 05:23 pm
Sweet!

I just placed an order for your finished LDR3v2 pre and look forward to what it can do! I have a Job 225 thats currently in the trading post here but for fun I put in back in the chain over the weekend to see how it could handle my new speakers and it sounds pretty good. I'm considering getting the Job 250 monoblocks with a little more power but has the same high gain as the 225 and from everything I've read is a great match with your passive pre.

Thanks for the order and yes we have several customers running our preamps with the Job 225 with great things to say about the pairing. I've been thinking of getting a Job as well based on all the positive feedback. Will have to look into dual 250's as well.
Title: wierd issues after firmware update
Post by: Crimson77 on 4 Mar 2015, 06:05 am
Hello!

I'm using a LDR3x preamp with 3 RCA inputs, and wonder how impedance adjustment can affect the sound. I downloaded the latest firmware ( for my case, it is LDR3X.V2.1_LDRx_3INPUT_217.hex ) and updated the firmware without problems. After some tries and playing around, I found the Impedance Number 3, no matter what impedance level I set, will make the preamp sound very loud! All other Impedance Number, i.e., 1, 2, 4, 5 , are normal and fine. Anyone has the same issue?

chang
Title: Re: wierd issues after firmware update
Post by: tortugaranger on 4 Mar 2015, 02:13 pm
Hello!

I'm using a LDR3x preamp with 3 RCA inputs, and wonder how impedance adjustment can affect the sound. I downloaded the latest firmware ( for my case, it is LDR3X.V2.1_LDRx_3INPUT_217.hex ) and updated the firmware without problems. After some tries and playing around, I found the Impedance Number 3, no matter what impedance level I set, will make the preamp sound very loud! All other Impedance Number, i.e., 1, 2, 4, 5 , are normal and fine. Anyone has the same issue?

chang

Hi Chang,

Based on your comment, I suspect that there may be some misunderstanding on how to set up the adjustable impedance. There are 5 possible impedance settings. The only one that comes configured is setting #1 which is already established at an impedance level of 20k. Settings 2-5 do not come pre-configured and you'll either get no sound (most likely) or some random sound level if you switch to one of these other settings without first configuring them.

In brief, here is the way you configure any setting number. With the unit turned on, press the left button on the remote. This will display the current setting number (1-5). Pressing the left button again will display the impedance level associated with that setting number. Setting #1 should be at 20. You can toggle between the setting number and the impedance level by repeatedly pressing the left button. If you are displaying the impedance setting (1-5) use the raise/lower buttons to switch between settings. If you are displaying the impedance level use the raise/lower buttons to adjust the desired impedance level between 1k and 99k for the setting number you're currently on. 

Here's the really important part and what I suspect might confuse people. Let's say you've just adjusted the setting #2 impedance level to the desired number - say 50k. In order for this to actually take effect, you must then do the following: a)  press the Enter/Center button (locks in the new 50k level for setting #2),  b) turn off the preamp,  c) then immediately run auto-cal.  If you don't do a), b) and c) in sequence before doing anything else nothing will happen and the #2 impedance will either not change from its prior level (if it was previously configured) or it won't be properly configured at all.

You have to repeat the above process for each of the impedance settings (except #1 which is already set up at 20k) in order to be able to switch between 5 different settings. If you just want to switch between setting #1 and #2 then you only have to configure #2 followed by auto-cal and you're good to go and should be able to switch back and forth between them.

It's entirely arbitrary what setting number you use and what impedance level (1k - 99k) you choose for each setting number. That said, I suggest leaving setting #1 at 20k (the baseline) and then configure one or more of settings 2-5 as you wish. Personally, I found it useful to configure setting #2 at 50k and setting #3 at 99k. That way you switch back and forth between these and decide if you think the sound gets better or not.

The unit will remember whatever setting number the preamp was last at and will use that impedance setting/level until you change either (but only after being properly configured per the above instructions).

It will be interesting to get feedback from users and see if a consensus develops on what is preferable.

Cheers,  :thumb:
Morten
Title: Re: Firmware Updates
Post by: robertopisa on 4 Mar 2015, 10:20 pm
Hello Morten, will this work also for double boards V2 in balanced configuration (master-slave)?
Thanks
-Roberto
Title: Re: Firmware Updates
Post by: tortugaranger on 4 Mar 2015, 10:28 pm
Hello Morten, will this work also for double boards V2 in balanced configuration (master-slave)?
Thanks
-Roberto

Yes, it will now once we got to rev 2.1.7.  Getting the dual mono/balanced boards to work right took some extra work but we've done a few dual/balanced sets with 2.1.7 and they're working as they should. Anyone with an earlier 2.1.X version on dual mono or balanced boards should update to 2.1.7.
Title: Re: Firmware Updates
Post by: robertopisa on 4 Mar 2015, 10:29 pm
Sorry I just read now that you already said that in the "Firmware Change Log" section of the download tab :)
Thanks
-Roberto

Yes, it will now once we got to rev 2.1.7.  Getting the dual mono/balanced boards to work right took some extra work but we've done a few dual/balanced sets with 2.1.7 and they're working as they should. Anyone with an earlier 2.1.X version on dual mono or balanced boards should update to 2.1.7.
Title: Re: Firmware Updates
Post by: robertopisa on 4 Mar 2015, 10:35 pm
Oops, another question... to be sure to operate correctly for dual mono balanced settings...

1. The new firmware must be still loaded separately on each individual board
2. The calibration procedure and setting of #2-#5 instead is handled by the master using the Apple remote as you described.

Is that correct?

-R
Title: Re: Firmware Updates
Post by: tortugaranger on 4 Mar 2015, 10:43 pm
Oops, another question... to be sure to operate correctly for dual mono balanced settings...

1. The new firmware must be still loaded separately on each individual board
2. The calibration procedure and setting of #2-#5 instead is handled by the master using the Apple remote as you described.

Is that correct?

-R

Yes to both. Once both boards have the same updated firmware the master communicates setting changes to the slave. It requires the Apple remote. Some customers have our earlier Tortuga remote which basically works but but the controls for adjustable impedance currently do not work with the Tortuga remote. The next firmware update will correct that.

Also, some customers have noted that the Tortuga remote (as opposed to the Apple) has a hair trigger with the latest firmware such that if you hold down a button like the power on/off too long the unit will turn on and then immediately turn off. That's because the Tortuga remote has automatic repeat whereas the Apple does not.
Title: V2 Boards Only: Special Instructions for upgrading to V2.1 Firmware
Post by: tortugaranger on 27 Jun 2015, 05:07 pm
Owners of V2 boards who are planning or have already upgraded to V2.1 firmware should read this carefully.

This only applies to V2 boards and not V2.1 boards.

The Issue: A key feature of the 2.1 firmware release is adjustable input impedance. V2 board owners can add this feature by upgrading to V2.1 firmware. All fine and good. However, upgrading directly from V2 to V2.1 firmware does not properly initialize the attenuation tables for each of the impedance settings 2 through 5. Only setting number 1 (20k by default) is properly initialized. So what you ask? Well, should you decide to switch from impedance setting #1 to either 2, 3, 4 or 5 (before properly configuring each of these) there's a very good chance your volume level will go to 100% and volume control will be unresponsive until you switch back to setting #1 or other properly configured setting, shut off the power or yank out the cables. Yeow you say! Indeed we say.

The Fix: To avoid "Yeow", the attenuation tables for all the 5 impedance settings need to be initialized. To do this you need to upload a special version of the firmware into your V2 board, let it boot up and initialize the tables. You'll know it's done after the boot up numbers on the displays stop showing up. After this is done, proceed to upload the regular latest version of the firmware and all should be well. You only have to do this one time. If you'v already upgraded your V2 to V2.1 firmware  we still recommend you run this initialization firmware. Initialization will overwrite any impedance setting you may have already configured and will reset the unit to setting #1 (20k).

You can find the firmware download files and related instructions on our website here: http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)
Title: Firmware Update - Bug Fix
Post by: tortugaranger on 17 Jul 2015, 06:28 pm
We just updated the firmware to version 2.1.8 as of 7.17.15 to fix a bug solely related to adjustable impedance.

Who Should Update: This update only applies if you are using adjustable impedance and wish to raise the impedance setting above 65k (up to max of 99k). If you're happy with impedance settings below 65k, you need not bother with this update.

The Issue:  When users tried to set the adjustable impedance level above 65k the setting level was not being reliably saved. Checking the setting immediately after saving it would sometimes show a different value than the one saved. This didn't happen with impedance values at or below 65k. The reason for this behavior was trying to pass a number that was bigger than could be contained properly by a 16 bit variable. Basically, a programming error.

The Fix: A minor edit to the software removed the 65k impedance restriction. Impedance should now be adjustable between 1k and 99k. Please note that with balanced systems the actual impedance will be twice the stated value (i.e. a 10k setting which yield a 20k input impedance).

You can find the firmware download files and related instructions on our website here: http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)
Title: Re: Firmware Updates
Post by: 33na3rd on 18 Jul 2015, 05:05 pm
Apple downloader coming in the near future?  :)
Title: Re: Firmware Updates
Post by: ThuanDB on 26 Jul 2015, 02:43 am
Hi Morten,

Please forgive my ignorance and/slowness, but after I've downloaded the 2.0 to 2.1 firmware as well as the boot loader, running it didn't have any effect (no connection between LDR and PC) even though the USB cable was hooking the LDR to the PC, and LDR was on.  Am I missing something?
Title: Re: Firmware Updates
Post by: tortugaranger on 26 Jul 2015, 02:29 pm
Hi Morten,

Please forgive my ignorance and/slowness, but after I've downloaded the 2.0 to 2.1 firmware as well as the boot loader, running it didn't have any effect (no connection between LDR and PC) even though the USB cable was hooking the LDR to the PC, and LDR was on.  Am I missing something?

First, you have a very recent build that has version 2.1.7 firmware. You already have a 2.1 device. Downloading and using anything related to 2.0 firmware is going backwards and is incompatible with your 2.1 machine so please don't try that.

Simply hooking up your PC to the preamp with a USB cable and running the Bootloader program on your PC will  do nothing. The ONLY time the preamp will be able to connect with the bootloader program on your PC is within the first 5 seconds after power is applied to the preamp. During those 5 seconds, the bootloader code on the preamp will talk to the bootloader program on your PC. To actually make a connection you have to press the Connect button on the PC bootloader program. If the Connect button isn't pressed within those 5 seconds, the bootloader program on the preamp will stop and the normal application firmware code on the preamp will start. If you missed the 5 second window, pull the power plug from the preamp, plug it back in again and try again.

Every preamp unit we ship is programmed this very same way so we know it works. This procedure is explained in detail in the software download section of our website. Look for the "Detailed Instruction" and expand that to read up on this procedure. http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)

Updating your firmware to the latest 2.1.8 will correct for a bug in the adjustable impedance that limited the max preamp setting to 65k rather than the 99k intended. If this isn't of interest to you then no need to update your firmware.
Title: Re: Firmware Updates
Post by: ThuanDB on 26 Jul 2015, 02:50 pm
You made me realize now that I missed the detailed instructions.  Thank you for the response.

Updates:  works perfectly, 99K ohms can now be saved and stay unchanged in any memory slot.  Thanks.
Title: 2.2.X Firmware Update & Apple Remote Changes
Post by: tortugaranger on 14 May 2016, 06:36 pm
Effective May 15, 2016 we are releasing version 2.2 of our firmware including changes in how the Apple Remote is used to control Tortuga Audio preamps. All new preamps will ship with the 2.2 firmware. Owners of existing V2 series preamps including the LDRx and LDRxB can upgrade to the 2.2 firmware if they wish.

This firmware update is a refinement of Tortuga Audio's V2 (and V2.1) generation preamp controller that was last released in January of 2015.

Highlights of this firmware update are as follows:

* Addition of auto-repeat to the Apple Remote providing ease of ramping volume up or down with a single press of the remote
* Improved Apple Remote functionality through a restructured control scheme
   * Balance adjustment is now the primary function of the left/right buttons along with volume control via raise/lower buttons
   * The Mute(play) button has been repurposed as a Control Mode button with the following control modes:
      * Input Adjust
      * Impedance Adjust
      * Display Brightness Adjust
      * Max Volume at Input Change Adjust
      * The Power On/Off button is now the Power On/Off-Mute button
* Improved control integration between preamp boards for balanced audio configurations
* Enhanced stability through numerous tweaks under-the-hood
* Better protection against spurious infrared noise sources that might cause false control inputs

The firmware won't be available for download until sometime tomorrow, Sunday 5.15.16. I will update with a link once it's ready.

More info can be found via the following 2 links:

A posted article saying substantially the same thing as above.
http://www.tortugaaudio.com/firmware-update-apple-control-changes/ (http://www.tortugaaudio.com/firmware-update-apple-control-changes/)

A new section in our documentation detailing the new Apple Remote controls.
http://www.tortugaaudio.com/documentation/#apple-2-2-x (http://www.tortugaaudio.com/documentation/#apple-2-2-x)

Happy to answer any questions.

Cheers,
Morten   :thumb:
Title: Re: 2.2.X Firmware Update & Apple Remote Changes
Post by: tortugaranger on 17 May 2016, 12:31 pm
The updated firmware files have been uploaded and are now available: http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)

Effective May 15, 2016 we are releasing version 2.2 of our firmware including changes in how the Apple Remote is used to control Tortuga Audio preamps. All new preamps will ship with the 2.2 firmware. Owners of existing V2 series preamps including the LDRx and LDRxB can upgrade to the 2.2 firmware if they wish.

This firmware update is a refinement of Tortuga Audio's V2 (and V2.1) generation preamp controller that was last released in January of 2015.

Highlights of this firmware update are as follows:

* Addition of auto-repeat to the Apple Remote providing ease of ramping volume up or down with a single press of the remote
* Improved Apple Remote functionality through a restructured control scheme
   * Balance adjustment is now the primary function of the left/right buttons along with volume control via raise/lower buttons
   * The Mute(play) button has been repurposed as a Control Mode button with the following control modes:
      * Input Adjust
      * Impedance Adjust
      * Display Brightness Adjust
      * Max Volume at Input Change Adjust
      * The Power On/Off button is now the Power On/Off-Mute button
* Improved control integration between preamp boards for balanced audio configurations
* Enhanced stability through numerous tweaks under-the-hood
* Better protection against spurious infrared noise sources that might cause false control inputs

The firmware won't be available for download until sometime tomorrow, Sunday 5.15.16. I will update with a link once it's ready.

More info can be found via the following 2 links:

A posted article saying substantially the same thing as above.
http://www.tortugaaudio.com/firmware-update-apple-control-changes/ (http://www.tortugaaudio.com/firmware-update-apple-control-changes/)

A new section in our documentation detailing the new Apple Remote controls.
http://www.tortugaaudio.com/documentation/#apple-2-2-x (http://www.tortugaaudio.com/documentation/#apple-2-2-x)

Happy to answer any questions.

Cheers,
Morten   :thumb:
Title: Re: Firmware Updates
Post by: tortugaranger on 17 May 2016, 03:17 pm
It's inevitable. We've found a couple of minor bugs both of which should have fixes very soon.

Auto-Repeat Caused by IR Noise – If you have a plasma TV or even an LCD TV near the preamp, you may experience the volume drifting either up or down by itself after a volume change. This is most likely due to external IR noise caused by a TV near the preamp. We are working on a fix for this which should be available soon.

Workaround:  turn off your TV when operating the preamp.

Max Volume at Input Change Set Too Low – The default value may be too low (as low as 5!) after updating to 2.2.0 firmware. This will be corrected in the next iteration.

Workaround: Press the Mode Control button 4 times. The displayed value will probably be 5. Use the raise button to increase this value to 35 or higher. Press enter to lock in the change.
Title: Re: Firmware Updates
Post by: glynnw on 17 May 2016, 06:26 pm
"Auto-Repeat Caused by IR Noise"  - Due to this I am hesitant to install the update.  My LCD TV sits less than 2' above the preamp and is used as the screen for the PC from which I get all my music.  Is there a way to de-install the update if I do have a problem?
Title: Re: Firmware Updates
Post by: tortugaranger on 17 May 2016, 07:13 pm
"Auto-Repeat Caused by IR Noise"  - Due to this I am hesitant to install the update.  My LCD TV sits less than 2' above the preamp and is used as the screen for the PC from which I get all my music.  Is there a way to de-install the update if I do have a problem?

I suggest you just hold off until we resolve. Have already fixed the false volume repeat but a few other bugs have been identified and are being resolved. Yes, can always reverse this with prior version if need be.
Title: Re: Firmware Updates
Post by: glynnw on 17 May 2016, 07:27 pm
Coolness - will wait until you tell us it is fixed.  Have relatives coming into town this  week and I am hesitant to change anything before they leave - whenever I move anything in my system, something else seems to go bad.  Probably Karma.

Thanks for all the continuing follow-up with your product - it just keeps getting better.
Title: Re: Firmware Updates
Post by: Gerry E. on 18 May 2016, 04:36 pm
I just want to echo glynnw's sentiments!  I love these upgrades, especially the volume repeat and balance control functionality.

Will you send out another e-mail when the download is available again or post here on the forum?  Thanks!

Gerry   
Title: Re: Firmware Updates
Post by: tortugaranger on 18 May 2016, 04:42 pm
I just want to echo glynnw's sentiments!  I love these upgrades, especially the volume repeat and balance control functionality.
Will you send out another e-mail when the download is available again or post here on the forum?  Thanks!
Gerry


We'll post an update here plus also in download page on the website. We've just about killed the few bugs and are in the process of testing/confirming. Should be done with that today/tomorrow.
Title: Re: Firmware Updates
Post by: Mr.Sneis on 20 May 2016, 07:25 am
If I diy a usb A to a 5 pin jumper block for j8 on the board (red/white/green/black wires).... is it ok to leave the sense/ID pin unused?
Title: Re: Firmware Updates
Post by: tortugaranger on 20 May 2016, 12:07 pm
If I diy a usb A to a 5 pin jumper block for j8 on the board (red/white/green/black wires).... is it ok to leave the sense/ID pin unused?

Yes, all you really need is ground, D+ and D- signals.

As of last night I think we've finished with cleaning up the various bugs. Waiting on one our beta testers to confirm this with his balanced preamp. Single ended has been confirmed solid. I expect to release rev 2.2.1 later today.
Title: Re: Firmware Updates
Post by: tortugaranger on 22 May 2016, 12:15 am
And so....here we are a week later ready to release rev 2.2.1, the first revision, of the 2.2 firmware upgrade. Unlike the original 2.2.0 release I believe we've shaken all the bugs out of this one and then some.

I want to give two big shout outs to TJHUB up in Wisconsin and nuhi all the way around in Croatia for all of their beta testing help and feedback this past week. You guys were super helpful and never waivered while we played software whack-a-mole day after day. The result is an upgraded control scheme that makes the Tortuga Audio preamps much simpler to operate.

I will post the firmware files in the morning along with some amendments to the documentation. I'll also pop out a newsletter update to let everyone know it's good to go now.

Cheers,
Morten

Title: Re: Firmware Updates
Post by: jtwrace on 22 May 2016, 12:17 am
Your responsiveness is awesome.   8) :thumb:
Title: Re: Firmware Updates
Post by: TJHUB on 22 May 2016, 04:35 am
And so....here we are a week later ready to release rev 2.2.1, the first revision, of the 2.2 firmware upgrade. Unlike the original 2.2.0 release I believe we've shaken all the bugs out of this one and then some.

I want to give two big shout outs to TJHUB up in Wisconsin and nuhi all the way around in Croatia for all of their beta testing help and feedback this past week. You guys were super helpful and never waivered while we played software whack-a-mole day after day. The result is an upgraded control scheme that makes the Tortuga Audio preamps much simpler to operate.

I will post the firmware files in the morning along with some amendments to the documentation. I'll also pop out a newsletter update to let everyone know it's good to go now.

Cheers,
Morten

Glad to help.  You are always great to work with, and I appreciate your efforts.

The new firmware control scheme is a really nice improvement.  Thanks! :thumb:
Title: Re: Firmware Updates
Post by: tortugaranger on 22 May 2016, 03:23 pm
Ok...we are good to go with the latest firmware update version 2.2.1 which is now available for download here.  (http://www.tortugaaudio.com/downloads/) Please read the note on the download page so you know what to expect.

More info on this upgrade from 2.1 to 2.2 firmware can be found here.  (http://www.tortugaaudio.com/documentation/#apple-2-2-x)

For those of you who have one, you'll be happy to know that we've retained the functionality of the legacy Tortuga remote. However, you'll find that the balance and balance reset buttons no longer work. But by using the left/right buttons to tweak balance I think you'll find it doesn't matter. Also, the 6 input select buttons no longer select inputs but each function the same as the Mode Select button on the Apple remote.
Title: Re: Firmware Updates
Post by: RDavidson on 22 May 2016, 05:48 pm
Morten,

apparently I'm missing something....or I'm not up to speed on computer stuff. Regarding things I'll need, the instructions state:

2.A USB cable that has a micro-B plug that fits into the USB receptacle on V2 board.

The Tortuga USB receptacle appears to be a standard A. Is there a micro B receptacle inside the unit? Or do I need to locate a male USB A to male USB A cable....or maybe a male USB A to female micro B adapter (http://www.amazon.com/Male-Micro-Female-Adapter-Black/dp/B009AWA3VK)? :scratch: Note, my unit is one of the custom builds Dave at ZenWave made late last year which utilized the latest Tortuga kit at that time. Hope you can help clear up my (and maybe others') confusion. Thank you.
Title: Re: Firmware Updates
Post by: tortugaranger on 22 May 2016, 05:55 pm
Morten,

apparently I'm missing something....or I'm not up to speed on computer stuff. Regarding things I'll need, the instructions state:

2.A USB cable that has a micro-B plug that fits into the USB receptacle on V2 board.

The Tortuga USB receptacle appears to be a standard A. Is there a micro B receptacle inside the unit? Or do I need to locate a male USB A to male USB A cable....or maybe a male USB A to female micro B adapter (http://www.amazon.com/Male-Micro-Female-Adapter-Black/dp/B009AWA3VK)? :scratch: Note, my unit is one of the custom builds Dave at ZenWave made late last year which utilized the latest Tortuga kit at that time. Hope you can help clear up my (and maybe others') confusion. Thank you.

If you have our USB connector cable connected to your board you will need a male A to male A.
Title: Re: Firmware Updates
Post by: RDavidson on 22 May 2016, 06:12 pm
Yes, I do. Thank you for clearing that up.
Very straight forward and glad I don't need to open the unit. I couldn't find info about the USB A input and didn't want to risk bricking my LDR board or something. You might add a provisional statement in the instructions that addresses the USB A input, just to be completely clear to everyone. :D
Title: Re: Firmware Updates
Post by: tortugaranger on 22 May 2016, 06:19 pm
Yes, I do. Thank you for clearing that up.
Very straight forward and glad I don't need to open the unit. I couldn't find info about the USB A input and didn't want to risk bricking my LDR board or something. You might add a provisional statement in the instructions that addresses the USB A input, just to be completely clear to everyone. :D

I'll update the documentation to clarify.

Also, since you have DIY board and the USB cable, please make doubly sure that the female plug end of that cable is connected the right way to the 5 pin J8 header on the board. The side of the female plug with the red wire should be right next to the microcontroller.
Title: Re: Firmware Updates
Post by: RDavidson on 22 May 2016, 06:39 pm
OK. Thanks again.
Title: Re: Firmware Updates
Post by: tortugaranger on 22 May 2016, 08:37 pm
A heads up for those with the earlier V2 preamp controller boards that have the micro-B USB socket.

As I was just reminded, it turns out there are 2 types of USB Micro B cables – the ones that only charge batteries, and the ones that are both data and charging-capable. They are not the same thing, and the stores often do not tell you which is which.

If you grab a USB micro-B cable and can't make a connection for uploading new firmware, there's a 99% chance  it's because you don't have a data-capable USB cable.  :duh:

Title: Re: Firmware Updates
Post by: Gerry E. on 23 May 2016, 06:24 pm
I installed the 2.2.1 firmware yesterday.  I followed the instructions closely but still ran into a few temporary bottlenecks.  The only one of significance was the actual download of the firmware .hex file itself.

Using Windows 7 and I.E. 11, when I tried to download the file, it would open it instead.  I could see the hex code and when I tried to save it as a .hex file, it would save it as an unusable .mht file.

After several tries with I.E., I tried the download using Mozilla Firefox and it worked the first time.  The rest was pretty much a breeze but don't forget to pair your Apple remote again.

The new remote functions are great.  I still don't know which one I like the most - the ease of the balance adjustment or the auto repeat of the volume control.   Good job Morten!  Thanks.

Gerry
Title: Re: Firmware Updates
Post by: tortugaranger on 23 May 2016, 07:23 pm
I installed the 2.2.1 firmware yesterday.  I followed the instructions closely but still ran into a few temporary bottlenecks.  The only one of significance was the actual download of the firmware .hex file itself.

Using Windows 7 and I.E. 11, when I tried to download the file, it would open it instead.  I could see the hex code and when I tried to save it as a .hex file, it would save it as an unusable .mht file.

After several tries with I.E., I tried the download using Mozilla Firefox and it worked the first time.  The rest was pretty much a breeze but don't forget to pair your Apple remote again.

The new remote functions are great.  I still don't know which one I like the most - the ease of the balance adjustment or the auto repeat of the volume control.   Good job Morten!  Thanks.

Gerry

What can I say.   I.E. strikes again.  Perhaps if you simply rename the saved *.mht file to *.hex it would be ok.  I've run across this once before with one customer who struggled with downloading the firmware file. He switched to Chrome and it worked normally.

If anyone runs into a problem downloading the firmware file drop my a note and I'll email it you. Presumably it will be ok as attachment under I.E. Hope springs eternal  :thumb:
Title: Re: Firmware Updates
Post by: glynnw on 23 May 2016, 08:46 pm
Just updated my single input DIY board, adjusted dimness, impedances, etc and all is well.  Will now use Sony remote instead of 1 of the 3 original remotes I have been hoarding.

2 comments - 1.  Using off/on button for mute not good when using the 12V trigger to turn on/off tube amps - fortunately I am all digital and can just pause the playback.

                       2.  When reconnecting unit to system it all works so much better when one connects the input cables to the input jacks and the output cables to the output jacks -  just trust me on this.

Thanks again, Morten, for all your work.  You can begin to catch up on your sleep now.
Title: Re: Firmware Updates
Post by: Mr.Sneis on 24 May 2016, 12:31 am
My update went smoothly on DIY board with DIY usb cable.  I'm all about the new remote scheme.

A few observations which are not a big deal:

On my particular setup I had about 1 second to click connect or it would behave like it was beyond 5 seconds (Windows 10)
Remote has to be paired again afterwards
When previously at volume 0 the unit would go to mute mode evident by blinking power LED; new firmware doesn't seem to do this
Previously when decreasing/increasing volume via remote the LED would blink as it received inputs making a tiny bit of noise as it did so; after update no more blinking and no more tiny noises

Wishlist:
A way to "reset" all settings to factory defaults (maybe this is just a reflash of firmware?)
Super wishful thinking but impedence adjustment procedure w/o display modules available

Thanks as always Morten!
Title: Re: Firmware Updates
Post by: tortugaranger on 25 May 2016, 01:28 pm
WISHLIST Etc. - Things missed and things requested that might make it into next minor update

1) Separate Mute & Off - As Glynn pointed out we completely neglected the 12V trigger out feature when we made mute & off the same thing. This needs to get fixed or else why have the trigger out feature. One way to do this is to make a single button press be Mute and a double press be Off.

2) Missing Status LED Actions - We overlooked the status LED in going to version 2.2. While the status LED is a legacy feature of the preamp controller board, several owners use the board in spartan installations that depend on the status LED as the sole means of feedback (no numerical displays). Things to add back:  a) blink at min volume (muted),  b) brief blink acknowledging command input

3) Factory Reset -  A way reset everything to a know default. I'm not all that keen on this since to do a true reset/initialization would erase the impedance/attenuation tables and require running autocal to get things working again. Making this available would invite accident resets as a downside.

4) Impedance Adjustment Without Displays - This is not going to happen. It's complex enough with displays. Without display feedback most users would get lost and frustrated.
Title: Re: Firmware Updates
Post by: doggie on 26 May 2016, 11:30 pm
Updated and all is well. I was even able to fix my Apple TV so that it did not respond directly when I used my LDR remote. Previously I literally almost rented a movie via the Apple TV while using the preamp!

Thanks for the hard work!
Title: Re: Firmware Updates
Post by: tortugaranger on 27 May 2016, 12:09 am
Updated and all is well. I was even able to fix my Apple TV so that it did not respond directly when I used my LDR remote. Previously I literally almost rented a movie via the Apple TV while using the preamp!

Thanks for the hard work!

Thanks. Very keen to find out what you did to your Apple TV to get it to ignore the preamp remote. The apple remotes all have an ID number between 0 and 255 which you can change. It made no sense to me that the Apple TV would respond to an apple remote that it wasn't paired with but they do to some extent.
Title: Re: Firmware Updates
Post by: mikebarney on 27 May 2016, 12:24 am
The separate mute and on/off functions are critical to me.  When I turn on my preamp, the 12v trigger fires up the whole system, same for powering down.  Any idea when that might be implemented?  I'm holding off doing the update for now.
Thanks,
Mike
Title: Re: Firmware Updates
Post by: tortugaranger on 27 May 2016, 12:42 am
The separate mute and on/off functions are critical to me.  When I turn on my preamp, the 12v trigger fires up the whole system, same for powering down.  Any idea when that might be implemented?  I'm holding off doing the update for now.
Thanks,
Mike


I expect to have that done and available sometime this weekend.
Title: Re: Firmware Updates
Post by: mikebarney on 27 May 2016, 01:45 am
Wow, thats fast!
Thanks very much,
Mike
Title: Re: Firmware Updates
Post by: TrungT on 27 May 2016, 11:28 am
First class support  :thumb:
Title: Re: Firmware Updates
Post by: tortugaranger on 30 May 2016, 05:31 pm
Firmware update 2.2.3 posted on 5.30.16  - here is the link (http://www.tortugaaudio.com/downloads/)

This update added back some features that didn't make the jump from 2.1 to 2.2. Most importantly it brought back muting as a stand alone feature. As some of you noted, turning the unit off as a form of muting defeated the Trigger Out feature which can be used to turn off amps etc. Without this latest change, muting would shut off the Trigger Out. Also, we did fix a creepy little bug in the channel balance adjustment.

This update is not a critical update. Only update if these features are important to you.

Change: When on, pressing menu button mutes/unmutes the unit and leaves it on, while holding menu button down longer turns the unit off.
Change: Added blinking display for when unit muted
Change: Added Panel LED flash to acknowledge when user switches control modes (for DIY users with no displays)
Fix: Corrected a bug which prevented channel balance from working the same in both directions

New Feature Request - A/B Testing  - We've received a request to add an A/B testing feature to the input switching. Currently the way it works is user selects input mode and then uses Raise/Lower buttons to select the desired input. Subsequently pressing Enter button locks in the selected input. If the input is different from current, the unit mutes, old input is shut off, new input turned on, and the unit unmutes. If we add the A/B testing feature, the user can optionally use the Left/Right buttons while in input mode. Doing so will immediately switch the inputs. If you're on 1, pressing Right will switch you to 2, pressing Left again will switch you back to input 1. Volume will not change using the fast A/B input switching mode and there will not not muting ramp down & ramp up of volume during the transition.
Title: Re: Firmware Updates
Post by: jkoestner on 31 May 2016, 01:27 pm
Do you think the new A/B feature being considered will make any type of "pop" through the amp and speakers?
Title: Re: Firmware Updates
Post by: tortugaranger on 31 May 2016, 01:40 pm
Do you think the new A/B feature being considered will make any type of "pop" through the amp and speakers?


Most definitely not especially with our finished preamps which use LDRs as discrete channel switches in lieu of mechanical relays. We will confirm this with testing of course by we have complete control over the timing of turning off the current input and turning on the new input. Given that LDRs are analog resistive devices with their own time constants for turning on and turning off they are inherently "soft" switchers.
Title: Re: Firmware Updates
Post by: doggie on 6 Jun 2016, 02:49 am
I am not on the very newest update but did the previous big one. I love it.

I have a feature request. Is it possible to have the display automatically turn off once the preamp is turned on and no user input is sensed within a specified time? Perhaps you could check status after that point by hitting enter?

I find that too many off my components have displays or LED's and it can be distracting. I realize that I can manually dim the readout each time but that gets a bit tedious if you play tracks from different CD's a lot and want to see and adjust the volume.

This is just a wish list. The preamp is great!
Title: Re: Firmware Updates
Post by: tortugaranger on 6 Jun 2016, 02:27 pm
I am not on the very newest update but did the previous big one. I love it.

I have a feature request. Is it possible to have the display automatically turn off once the preamp is turned on and no user input is sensed within a specified time? Perhaps you could check status after that point by hitting enter?

I find that too many off my components have displays or LED's and it can be distracting. I realize that I can manually dim the readout each time but that gets a bit tedious if you play tracks from different CD's a lot and want to see and adjust the volume.

This is just a wish list. The preamp is great!

Others have requested a similar feature so we'll be adding that to the next version. Given how we've restructured the control scheme this will be fairly painless to implement and the user can easily use or ignore the feature.

Currently there are 5 control modes with volume control being the default. Display brightness adjustment is one of the 4 other modes. When you select that mode you see a number between 1 and 15 on the right display which you can adjust up/down via the raise/lower buttons on the remote. The plan is to add a display timeout feature wherein after a preferred number of seconds the display will go dark.  While in the display mode using the left/right buttons the user will be able to adjust the timeout setting which will be shown in the left display. 0 seconds means the display stays on all the time (the default). The user can adjust the timeout value between say 10 seconds and 99 seconds. When the display is off, pressing any button on the remote will turn the display back on and that button press will be otherwise ignored (buttons will only work normally when display is on).

As of now the new features coming with the next version include:

1) Fast A/B input switching
2) Automatic display shutoff
Title: Re: Firmware Updates
Post by: doggie on 6 Jun 2016, 04:49 pm
Great! Thanks for being so responsive. Much appreciated.
Title: Re: Firmware Updates
Post by: kernelbob on 6 Jun 2016, 09:41 pm
Hi Morten, good to know I'm not the only one who would like to have the capability to have the display go dark.  One thing, I hope the minimum time is less that the ten seconds you mention.  Two seconds is plenty of time to press another key.  If someone wants the display to wait longer to go dark, well that's what the customizable delay is for.

Thanks, Robert
Title: Re: Firmware Updates
Post by: tortugaranger on 8 Jun 2016, 05:19 pm
Hi Morten, good to know I'm not the only one who would like to have the capability to have the display go dark.  One thing, I hope the minimum time is less that the ten seconds you mention.  Two seconds is plenty of time to press another key.  If someone wants the display to wait longer to go dark, well that's what the customizable delay is for.

Thanks, Robert

I don't know if 10 seconds is reasonable but I suspect 1 or 2 seconds is too short and it would become an annoying process of repeatedly turning the display back on while messing with adjustments. I'll establish a practical lower time-out limit as part of final testing. Should have this all worked out by the weekend.
Title: Re: Firmware Updates
Post by: kernelbob on 8 Jun 2016, 10:49 pm
Hi Morten,

I'm only suggesting that since you've indicated that you're going to allow the user to select a delay of up to 99 seconds, why limit the low end of the delay time to 10 seconds?  I've got a device that shuts off the display after 3 seconds.  After becoming comfortable with the controls, even that seems longer than ideal... to me.  My point is each to his own.

Let me say this, you've been exceptionally open to (and patient with) customer feedback.  I appreciate all the extra work you've done to add the many refinements to Tortuga products that set them apart from the field.

Best,
Robert
Title: Re: Firmware Updates
Post by: tortugaranger on 14 Jun 2016, 03:03 pm
Hi Morten,

I'm only suggesting that since you've indicated that you're going to allow the user to select a delay of up to 99 seconds, why limit the low end of the delay time to 10 seconds?  I've got a device that shuts off the display after 3 seconds.  After becoming comfortable with the controls, even that seems longer than ideal... to me.  My point is each to his own.

Let me say this, you've been exceptionally open to (and patient with) customer feedback.  I appreciate all the extra work you've done to add the many refinements to Tortuga products that set them apart from the field.

Best,
Robert

I've got the  display timeout all tested and working now. You'll be pleased to know that you can adjust it all the way down to a 1 second timeout if you like. At 1 second, if you are quick after "waking it up" you can raise/lower volume quickly enough to keep the display lit and then when you stop it goes dark within a second.

The key to this being practical is to suspend display timeout when in any control mode other than volume control.

Will post update on this soon as I have uploaded the newest firmware to the website.


Title: Re: Firmware Updates
Post by: DaveC113 on 14 Jun 2016, 05:38 pm
One more wish...

Sometimes the displays blink rapidly because of optical "noise" from the plasma, or even the way light shines through the window sometimes. The displays will blink rapidly forever unless you hit the middle button on the apple remote. If the preamp is in a mode other than normal/default where volume is adjusted and no input is given for 30 seconds the preamp should default back to normal setting. This would make the issue with optical noise much less of an issue.

I also covered the remote sensor with a layer of two of skivved teflon tape, which is tinted, and this keeps the issues with optical noise down but it's still an issue sometimes.



Title: Re: Firmware Updates
Post by: tortugaranger on 14 Jun 2016, 05:42 pm
One more wish...

Sometimes the displays blink rapidly because of optical "noise" from the plasma, or even the way light shines through the window sometimes. The displays will blink rapidly forever unless you hit the middle button on the apple remote. If the preamp is in a mode other than normal/default where volume is adjusted and no input is given for 30 seconds the preamp should default back to normal setting. This would make the issue with optical noise much less of an issue.

I also covered the remote sensor with a layer of two of skivved teflon tape, which is tinted, and this keeps the issues with optical noise down but it's still an issue sometimes.

Hi Dave,

Do you know what rev firmware you have? When the unit powers up what are the first 3 digits shown on the right display....or in the case of rev 2 firmware what is the 3 digit number shown via both displays together? The reason I'm asking is I believe the latest firmware is less susceptible to noise than before. Yours would be a good test case to confirm/refute that. I don't have a plasma TV to bombard it with but I used to be able to get it to respond to a fluorescent lamp inches away from the IR receiver. Now it ignores it. 

Cheers,
Morten
Title: Re: Firmware Updates
Post by: DaveC113 on 14 Jun 2016, 05:48 pm
Hi Dave,

Do you know what rev firmware you have? When the unit powers up what is the first 3 digits show on the right display....or in the case of rev 2 firmware what is the 3 digit number show via both displays together? The reason I'm asking is I believe the latest firmware is less susceptible to noise than before. Yours would be a good test case to confirm/refute that. I don't have a plasma TV to bombard it with but I used to be able to get it to respond to a fluorescent lamp inches away from the IR receiver. Now it ignores it. 

Cheers,
Morten

Not sure exactly, but it must be the version right before the new release.

I'll do the update at some point but need an A to A USB cable, which is technically not supposed to exist but I know it's possible to get them.
Title: Re: Firmware Updates
Post by: jtwrace on 14 Jun 2016, 05:54 pm
Not sure exactly, but it must be the version right before the new release.

I'll do the update at some point but need an A to A USB cable, which is technically not supposed to exist but I know it's possible to get them.
https://www.firefold.com/usb-cables-a

Or use an adapter.
Title: Re: Firmware Updates
Post by: tortugaranger on 14 Jun 2016, 06:00 pm
I'll do the update at some point but need an A to A USB cable, which is technically not supposed to exist but I know it's possible to get them.


They exist. I have a bunch in stock here. I'll pop one in the mail to you today. No charge.
Title: Re: Firmware Updates
Post by: DaveC113 on 14 Jun 2016, 06:18 pm

They exist. I have a bunch in stock here. I'll pop one in the mail to you today. No charge.

Thanks, much appreciated!  :thumb:
Title: Re: Firmware Updates
Post by: tortugaranger on 17 Jun 2016, 03:22 pm
Most Recent Firmware Update | Version 2.2.5 | June 17, 2106

This purpose of this update is the addition of 2 new features that users have requested plus one minor bug fix that only applies to balanced preamps. As such this is not a critical update. This update skips a version (2.2.4) which was shipped in only a single preamp and included the Fix discussed below.

Hope springs eternal but I really think this will be the last iteration of the version 2.2 series for a while now. We've gone through the usual post-release bug kill and everything appears to be stable.

New: Fast Input Switching - While in Input adjust mode, user now has option to do use fast switching between inputs by using the Left/Right buttons on the remote rather than the normal Raise/Lower followed by Enter. When using the Left/Right buttons the inputs transition within less than a second without any muting/unmuting. When using fast switching the volume will immediately go the volume level last associated with the selected input.

New: Display Timeout - When in Display adjust mode user can now optionally set the time (in seconds) before display turns off after last user input. Adjustment is between 1 and 99 seconds using the Left/Right remote button. Setting timeout to zero (0) disables the timeout feature. Display timeout only works when in volume adjust mode and is disabled when in any other control mode such as input adjust, impedance adjust, display adjust etc. After updating you should check this setting since it may not be zero (off) by default.

Fix: Turn Off (Balanced Preamps) - The new preamp turn off function by pressing/holding the Menu button that introduced in version 2.2.3  was not working properly for balanced units. This update fixes that.

More Info On Fast Input Switching

Fast Input Switching was introduced at the request of users who wanted to be able to do A/B testing with difference sources. Fast input switching overrides the normal automatic and relatively slow sequence of first muting the current input, switching inputs, and then ramping the volume back up. Fast switching has only been tested with Tortuga preamps that use LDRs for input switching - we have not tested this with our DIY relays and kits.  LDRs are inherently slow switches compared to relays. While they turn on relatively quickly, they are much slower to turn off. Because of the slow turn off time, fast switching includes a brief transition delay of 200 milliseconds. This delay is barely perceptible but avoids any potentially harmful artifacts such as pops or bumps to your speakers. Users are cautioned to avoid switching between inputs where the current input is at a low volume level and the new input was previously at a high volume level. The preamp will abruptly go to the volume level last associated with the new input. As it does so the volume of the current input may surge slightly before it fully turns off.

Firmware info and downloads can be found here:  http://www.tortugaaudio.com/downloads/
Title: Re: Firmware Updates
Post by: doggie on 18 Jun 2016, 08:11 pm
Can you please point me to the updated Apple Remote instructions?

I successfully updated to the newest firmware to take advantage of the display timeout but cannot find the newest information.

I love my preamp and your service is fantastic but I find the Support web pages  to be very confusing. It might help to have the most current information on just the first page with just links to older information and DIY stuff.

Much appreciated. Thanks!

Paul
Title: Re: Firmware Updates
Post by: tortugaranger on 18 Jun 2016, 09:32 pm
Can you please point me to the updated Apple Remote instructions?

I successfully updated to the newest firmware to take advantage of the display timeout but cannot find the newest information.

I love my preamp and your service is fantastic but I find the Support web pages  to be very confusing. It might help to have the most current information on just the first page with just links to older information and DIY stuff.

Much appreciated. Thanks!

Paul

Hi Paul,

We just now finished updating the Apple Remote instructions so that they are current with rev 2.2.5.  You can access this section via this link: http://www.tortugaaudio.com/documentation/#apple-2-2-x (http://www.tortugaaudio.com/documentation/#apple-2-2-x)

Or...on at the top of documentation page just expand drop down menu item on the left entitled "Remote Controls" and then select "Apple Remote | 2.2".   It  is a bit confusing since version 2.2 is in section 2.1 and visa versa.

Always appreciate feedback. Thanks.  :thumb:
Title: Re: Firmware Updates
Post by: doggie on 25 Jun 2016, 11:34 pm
Thanks. Up and working well...
Title: Firmware Update - 2.2.8
Post by: tortugaranger on 28 Aug 2016, 01:03 pm
A firmware update is available on our website via this link: http://www.tortugaaudio.com/downloads/ (http://www.tortugaaudio.com/downloads/)

This update is a compilation of versions 2.2.6, 2.2.7 and 2.2.8 with the former two rolled up in the latest 2.2.8.

This is not a critical update but it does kill a few minor bugs while generally improving stability and control especially with the Encoder. Volume control via the encoder is now smoother and more granular with each volume step more clearly corresponding to the encoder’s position detents (stopping points). It also adds back the missing encoder balance adjust feature which somehow got left out when we released version 2.2.0 firmware. We have also implemented polarity reversal but this applies only to our LDRxB balanced preamp model and requires some special hardware modifications to the LDRxB for phase reversal to work. Please contact us if you’re interested in the LDRxB and balanced preamp phase reversal.

Version 2.2.8
Fix:  Encoder control inputs failed to wake up the display after it timed out and turned off (works fine with remote control as is).
Version 2.2.7
Change: Made encoder turning interrupt driven rather than poling to improve control response
Fix: Restored missing balance adjust control functions to Encoder
Tweak: Improved encoder decode logic for smoother stepping synced with detents
Tweak: Reduced encoder input change threshold from 5 to 2 steps when using encoder to change inputs
Version 2.2.6
New: Implemented polarity reversal for LDRxB models only - requires special version of firmware - also requires hardware modifications

How do you know what version of firmware you have? Each time you apply power to the preamp (not turn on, but power up), the first 3 digits displayed during boot up is your firmware number.
Title: Re: Firmware Updates
Post by: tortugaranger on 30 Sep 2016, 07:18 pm
We found (correction: a customer found  :nono:) a minor firmware bug that's really not a problem per se but might look like it is.

Here's the issue: If you happen use the preamp display timeout feature and run autocal there's a random possibility that at some point in the autocal cycle the display will blank out making it appear as though autocal ended prematurely. In fact it does not end but how would you know? The problem is a bit of missing logic that fails to ignore the display timeout feature during autocal.

The fix: We will soon update the firmware to version 2.2.9 with this corrected.

The work around:  1) Ignore it;  2) Turn display timeout off (set  it to 0 seconds) before running autocal
Title: Re: Firmware Updates
Post by: Mr.Sneis on 7 Oct 2016, 09:58 pm
Morten,  is there any way to have the default volume level lowered?  I don't have an LCD display setup but I am guessing it seems to be around the 50% mark after power up for me which is fairly loud; I then drop the volume myself and all is OK.  Otherwise my previous volume level isn't really sticking as I cut the power on shut-down if that makes sense.
Title: Re: Firmware Updates
Post by: tortugaranger on 8 Oct 2016, 01:49 pm
Morten,  is there any way to have the default volume level lowered?  I don't have an LCD display setup but I am guessing it seems to be around the 50% mark after power up for me which is fairly loud; I then drop the volume myself and all is OK.  Otherwise my previous volume level isn't really sticking as I cut the power on shut-down if that makes sense.

Yes, provided you have the updated 2.2.x firmware (which is currently available for download version 2.2.eight). If you don't have visual feedback via displays you can still adjust the max starting volume although it make take some trial and error doing it blind.

The default setting is step 35 which is roughly half volume.

To access the "max volume on change" adjust control, press the mode button (lower right hand button on apple remote) 4 times. If you have the single input firmware version press it only 3 times. Then use the lower button to reduce the default 35 setting however many number of steps you want. For example press the lower button 10x to achieve a setting of 25. Then press the center button to lock in this new setting and return to normal volume control mode.

To confirm the new setting raise the volume to "loud"  then change an input or turn the unit off and on again and note the new volume level upon start or after changing input.
Title: Re: Firmware Updates
Post by: Mr.Sneis on 8 Oct 2016, 02:51 pm
Thank you for the explanation Morten!  Happy to report I think it worked perfectly!
Title: Re: Firmware Updates
Post by: craig sawyers on 4 Jan 2017, 10:08 am
Hi Morten

Just a heads up that the software download tab seems to be broken - if you click it, nothing happens.

Craig
Title: Re: Firmware Updates
Post by: tortugaranger on 4 Jan 2017, 02:51 pm
Hi Morten

Just a heads up that the software download tab seems to be broken - if you click it, nothing happens.

Craig

Thanks for the heads up Craig. It's been fixed and should be working now.

Morten
Title: Re: Firmware Updates - V2/2.1
Post by: germamiga on 6 Mar 2019, 01:14 pm
hello sorry for my poor English.
i want update firmware ...of my ldr3 v2.1 but i have ldr io board relay.......i put diy v2 board firmware or ldr v2 -3 ldrx input....... ???

thanks for response
Title: Re: Firmware Updates - V2/2.1
Post by: tortugaranger on 6 Mar 2019, 08:40 pm
hello sorry for my poor English.
i want update firmware ...of my ldr3 v2.1 but i have ldr io board relay.......i put diy v2 board firmware or ldr v2 -3 ldrx input....... ???

thanks for response

If you have a 2/2.1 board connected to one of our IO3 input relay boards then use the DIY V2 board firmware. If you accidentally use one one the other versions it won't hurt the board/preamp but the input switching will not work right or won't work at all. In that case just update with  the correct version and it should be ok.
Title: Re: Firmware Updates - V2/2.1
Post by: germamiga on 7 Mar 2019, 03:42 pm
ok ! thanks  :D
Title: Re: Firmware Updates - V2/2.1
Post by: craig sawyers on 22 Jun 2020, 10:07 am
Hi Morten

Reviving a moribund thread to ask a simple question. I have used and massively enjoyed my DIY balanced V2.1, with relay output boards for quite a few years. But I have been derelict in updating the firmware. The controller returns 21812021 on power up. Since the eternity that I have not updated the firmware, I see that you have moved all the firmware updates to an ftp server.

The question is, what is the software version I need to download?

Kind regards

Craig
Title: Re: Firmware Updates - V2/2.1
Post by: tortugaranger on 22 Jun 2020, 04:58 pm
Hi Morten

Reviving a moribund thread to ask a simple question. I have used and massively enjoyed my DIY balanced V2.1, with relay output boards for quite a few years. But I have been derelict in updating the firmware. The controller returns 21812021 on power up. Since the eternity that I have not updated the firmware, I see that you have moved all the firmware updates to an ftp server.

The question is, what is the software version I need to download?

Kind regards

Craig

Hi Craig,

We've updated our online documentation so that it now also includes the firmware instructions/files for the V2/V2.1 models.
I refer you to the following link:  https://tortugaaudio.com/docs-category/firmware/ (https://tortugaaudio.com/docs-category/firmware/)
You'll see firmware info for both the V25 and V2 types listed. Ignore the V25 info.

Cheers,
Morten
Title: Re: Firmware Updates - V2/2.1
Post by: craig sawyers on 22 Jun 2020, 05:45 pm
I think I've answered my own question - the DIY version of 2.2.8.

It is on the Tortuga website, but I only found it by a google search.....

Craig
Title: Re: Firmware Updates - V2/2.1
Post by: tortugaranger on 22 Jun 2020, 06:17 pm
I think I've answered my own question - the DIY version of 2.2.8.

It is on the Tortuga website, but I only found it by a google search.....

Craig


Right, there's only ever been 1 version of the firmware listed at any given time. It happens to be 2.2.8 which has been stable now for 2+ years. However there are versions of 2.2.8 for different V2 based products. I think when you looked for it on the website earlier it wasn't there at all because we're in the process of converting over to a new online product documentation system and the V2 firmware info was in limbo.
Title: Re: Firmware Updates - V2/2.1
Post by: craig sawyers on 22 Jun 2020, 06:22 pm
Our two replies must have crossed! Funnily enough when I looked at my downloads file, I actually had the file already! Anyhow - thanks for keeping support available for those of us running older versions of your excellent product line.

Kind regards

Craig
Title: Re: Firmware Updates - V2/2.1
Post by: craig sawyers on 22 Jun 2020, 08:18 pm
OK, firmware went in to both halves of the balanced unit. Needed to re-pair the Apple. Got used to remote buttons being repurposed, and tried to do an autocal. But it has frozen at cal step 2, step 1. Tried power cycling, but the same happens.

The net effect is that the RH channel works, but the LH channel is silent.

Any idea what is going on?

Craig
Title: Re: Firmware Updates - V2/2.1
Post by: tortugaranger on 22 Jun 2020, 08:33 pm
OK, firmware went in to both halves of the balanced unit. Needed to re-pair the Apple. Got used to remote buttons being repurposed, and tried to do an autocal. But it has frozen at cal step 2, step 1. Tried power cycling, but the same happens.

The net effect is that the RH channel works, but the LH channel is silent.

Any idea what is going on?

Craig

It's been quite a while since we've worked on the V2's but as I recall when doing a big firmware update on 2 boards used in balanced configuration you need to initially deal with each board as a stand alone board, get them both up and working by themselves first with display attached including running calibration 2-3 times each and only then connect them back up in balanced master/slave mode knowing they are already good to go by themselves.

Also, the fact that the left channel is not responding while the right is OK is the #1 tell that the 2 boards are not in sync. They both have to have the same firmware and be good to go alone before playing well together.

Having just re-read your note it's entirely possible that the upgrade will reveal a marginal LDR and you'll get stuck getting through cal. To confirm it's one of the LDRs gone wonky, you can swap them around and see if that unsticks the stuck cal.
Title: Re: Firmware Updates - V2/2.1
Post by: craig sawyers on 22 Jun 2020, 08:46 pm
Thanks Morten. I'll disconnect the master/slave connection and run can on each one separately. I assume that with a dual display that should be straightforward?
Title: Re: Firmware Updates - V2/2.1
Post by: tortugaranger on 22 Jun 2020, 08:56 pm
Thanks Morten. I'll disconnect the master/slave connection and run can on each one separately. I assume that with a dual display that should be straightforward?

Ideally just swap the display cable over to the other board while doing this. Make sure you pull the jumper on the slave board to make it operate like a master and then reverse that when going back to balanced.
Title: Re: Firmware Updates - V2/2.1
Post by: craig sawyers on 22 Jun 2020, 09:25 pm
OK - that makes complete sense, thanks. It is pretty late here in the UK, but will tackle this tomorrow and let you know what I find out. Trying to mess with electronics late at night is never a good idea ;-)
Title: Re: Firmware Updates - V2/2.1
Post by: craig sawyers on 23 Jun 2020, 10:46 am
OK - totally sorted. Problem was both master and slave were failing autocal at different places. The place in autocal each one froze could be changed by swapping around modules.

You pointed out that this could be to do with LDR characteristics changing to the extent that autocal failed. Oddly it seemed to work in 2.1.8, but 2.2.8 seems to be more sensitive to significant mismatch. Both units returned 228 by the way, so the correct version was in both boards.

Now - I just happened to have a stock of the correct LDR's. Back before I found Tortuga, I was intending to make my own LDR control. Very simple - but to get decent tracking required LDR selection. Hence the stock of LDR's!

So I spent a couple of hours desoldering the old LDR's and replacing them with new. Which was a great success - autocal worked perfectly on both boards run as separate controllers, and then autocal'd perfectly re-wired as a balanced contoller!

The upshot is that the sound quality is dramatically improved. So apart from characteristic drift, something else must have been going on with distortion or something similar.

So thanks for the diagnosis Morten - it was right on the money.
Title: Re: Firmware Updates - V2/2.1
Post by: tortugaranger on 23 Jun 2020, 12:08 pm
OK - totally sorted. Problem was both master and slave were failing autocal at different places. The place in autocal each one froze could be changed by swapping around modules.

You pointed out that this could be to do with LDR characteristics changing to the extent that autocal failed. Oddly it seemed to work in 2.1.8, but 2.2.8 seems to be more sensitive to significant mismatch. Both units returned 228 by the way, so the correct version was in both boards.

Now - I just happened to have a stock of the correct LDR's. Back before I found Tortuga, I was intending to make my own LDR control. Very simple - but to get decent tracking required LDR selection. Hence the stock of LDR's!

So I spent a couple of hours desoldering the old LDR's and replacing them with new. Which was a great success - autocal worked perfectly on both boards run as separate controllers, and then autocal'd perfectly re-wired as a balanced contoller!

The upshot is that the sound quality is dramatically improved. So apart from characteristic drift, something else must have been going on with distortion or something similar.

So thanks for the diagnosis Morten - it was right on the money.


 :thumb: