[tortugaranger]

Customers have asked if the Tortuga Audio passive preamps have a home theater (HT) bypass? In terms of a simple bypass switch the answer is no. And it's highly unlikely we'd ever add such a switch. But we can still achieve HY bypass without a switch.

The LDRx passive preamp can be effectively bypassed by simply running the volume level up to 100% when using a HT receiver. At that point the passive presents approximately ~2-300 ohms of series resistance and over 100k of shunt resistance to ground - as if it's hardly there. You know you're at 100% volume when the Status LED is blinking (it also blinks at 0% - muted). In this mode, volume is controlled solely by the HT receiver.

However, the above scenario presents the potential risk of forgetting that the preamp is at max volume when switching back to your DAC or other source input and possibly damaging your speakers.

The solution is a software change that will now become standard in all of our preamp units sold going forward. Any change of input will automatically set the volume level down to 50% of scale if the volume was greater than 50% prior to the input change. So if you happen to be in full volume HT bypass mode and you switch back to your DAC, the volume will automatically reset to 50% of scale prior to the DAC input being connected thus probably save your speakers not to mention avoiding scaring the hell out of ya from the full volume sonic blast.

Not a big fan of adding features just to add features, but this one's a no-brainer.    At least going forward.

Cheers,
Morten

[WireNut]

That's pretty cool   

[Austin08]

That is cool. People from Oppo should learn more about this.

[wilsynet]

That's clever.

[tortugaranger]

Cool and clever! Thx. I'll take that all day long. 

[gregfisk]

Morten,

Yes, very cool and clever, this is something I've been meaning to ask about. Can I send my board in for an update?

Thanks,

Greg

[wilsynet]

Have you considered saving the position of the volume knob on a per input basis?  That is, every time you switched away from an input, if the volume position was different than the previously saves volume position for that input, then it would save the new one.  When you switch back, rather than restore to mid-volume, it would restore to saved volume.

[tortugaranger]

Have you considered saving the position of the volume knob on a per input basis?  That is, every time you switched away from an input, if the volume position was different than the previously saves volume position for that input, then it would save the new one.  When you switch back, rather than restore to mid-volume, it would restore to saved volume.

That is now included in the software for the ldr3x.V2 preamp controller board. When you switch to another input, the volume level is reset to whatever level was associated with that input the last time it was used. However, that initial volume level reset is still limited to step 35.

As an extreme example, if the last time you listened to input #2, you happened to enjoy it at max volume (step 70) and then changed to another input, when you subsequently switch back to input #2, it will not start off at step 70 (max volume) but will instead start out at step 35.

Based on my own personal tastes and behavior I find that I'm changing the volume level quite often depending on mood, what I'm otherwise doing, and what I'm listening to. So for me, the benefit of preset (or remembered) volume levels associated with each input is largely lost on me. The first thing I do when turn on my rig, change inputs, or change what's playing, is I adjust the volume level. Which with a remote is so easy to do.

But I do take comfort knowing that the next time I turn on my system, it will thankfully NOT start up where I left off last night listening to Daft Punk at step 60! Or for those with home theater, you don't have to remember that you last left it at 100% volume.

[sfox7076]

What would happen if you calibrated your HT system with the TOrtuga locked at 35 instead of at 70?  I ask because I just bought a Tortuga to use as an HT Bypass/two input pre (DAC and for my turntable) and would like to set it up at 35 so that it is pretty easy to use for my wife...

Shawn

[tortugaranger]

What would happen if you calibrated your HT system with the TOrtuga locked at 35 instead of at 70?  I ask because I just bought a Tortuga to use as an HT Bypass/two input pre (DAC and for my turntable) and would like to set it up at 35 so that it is pretty easy to use for my wife...

Shawn

The level you set the Tortuga preamp to when used in HT bypass mode can be whatever you want it to be. It's not automatic. You have to deliberately make the adjustment. Usually in HT bypass the bypassed pre is set to max output (70 in the case of Tortuga) and your HT controls the volume. If you set the pre at 35 you're limiting the max volume that the HT can achieve when it's cranked up to max.  Which may be fine if that's what you're after.

The Tortuga preamps have no actual HT Bypass in terms of true bypass switch so setting them up to max/70 is simply a recommended approach to give your HT full volume control. When you switch to another input the volume automatically gets reduced to 35 to avoid blowing out your speakers should you forget to reduce volume down from 70.

[sfox7076]

Right.  That's what I assumed.  I just acquired a Tortuga LDR3v2.  Will see what 50% attenuation will do.  If it doesn't work, I will use something else as a source selector for it.  Is there anyway to have one input locked at 70, but the rest at 35?  I know the answer is no, but I guess I would request that option...