AudioCircle

Industry Circles => Tortuga Audio => Topic started by: glynnw on 2 Nov 2020, 02:57 am

Title: Recommended power supply for LDR300X.V3 passive
Post by: glynnw on 2 Nov 2020, 02:57 am
I remember that at one time you said the wall wart supplied with the passive was as good as an aftermarket linear supply and you also once offered a battery power supply.  What do you think is the best solution for a power supply for your new passive?
Title: Re: Recommended power supply for LDR300X.V3 passive
Post by: glynnw on 21 Dec 2020, 10:57 pm
Got no reply so I ask again.  Does anyone have a power supply that they KNOW sounds better than using the stock wallwart?  To be more specific, a supply that costs under $1K.  While I find the stock system to be the best volume control I have ever used, like all of us, I want MORE, MORE MORE!
Title: Re: Recommended power supply for LDR300X.V3 passive
Post by: MttBsh on 21 Dec 2020, 11:16 pm
Got no reply so I ask again.  Does anyone have a power supply that they KNOW sounds better than using the stock wallwart?  To be more specific, a supply that costs under $1K.  While I find the stock system to be the best volume control I have ever used, like all of us, I want MORE, MORE MORE!

AudioCircle member LordCloud recently stated that using a battery power supply improved the sound of his Tortuga passive.
https://www.audiocircle.com/index.php?topic=173864.0
Title: Re: Recommended power supply for LDR300X.V3 passive
Post by: kernelbob on 22 Dec 2020, 01:04 am
I'm using a Tortuga LDRxB balanced unit for the main controller in my biamplified system.  The LDRxB is directly connected via XLRs to tube monoblocks driving the mid/treble speaker inputs.  The second set of XLR ouputs on the LDRxB connect to a LDR1B (also balanced) which is used to adjust the signal level of the solid state bass amps. Since we're dealing with passive controllers, managing impedance is a must.  I've added a Tortuga Tube Buffer ahead of the LDR1B.  This is needed since my bass amps have a very low imput impedance (fine tuning the bass signal level with the LDR1B remote is such a nice feature to have).  The tube buffer isolates that low impedance from being felt by the LDRxB which would otherwise sap dynamics.

Both the LDRxB and LDR1B come with AC to DC wallworts.  Morten has [had?] an optional standalone battery DC source.  However, I decided to cobble together my own DC battery power supply that feeds both my LDRxB and LDR1B.  It's a simple thing to assemble.  These are the parts: a 12 volt battery (I use an Optima deep cycle marine battery, overkill to be sure, but definitely will not sag); the smallest trickle charger you can find (I use a Genius G750); a barrel connector with attached cable for the DC connection to the Tortuga (I use two sets of inputs for both controllers of course).  One thing, make certain that you have the correct ID and OD sized barrel connector.  Morten will confirm this if it isn't already on the Tortuga website.  I don't recall the specs.

Both the trickle charger and the Tortuga DC input leads are connected and active 24/7/365.  Keep in mind that selecting "Off" from the Tortuga remote does not power off the unit.  A full power off only happens when you physically disconnect the power input connector.  The only way I can tell if the trickle charger is active is that the status light changes from green to blinking red.  There is no sonic impact from the charger charging.  Assembling the battery power source was easy.

Benefits?  In my system the improvement was obvious.  The sound is more relaxed, more dynamic, and with a lower noise floor.  A friend of mine also has a Tortuga controller.  He opted to get the Tortuga battery power supply which provided similar sonic improvements.  One point, I chose a sealed battery since the it's in a corner of my listening room.

Addendum:
Just in case someone build this do-it-yourself battery supply, there's one more last essential step.  Before you connect your battery to the Tortuga, use a voltmeter to confirm that the barrel connector's power is the same polarity as the one from the original wallwort.  Trust but verify.

Hope this helps,
Robert
Title: Re: Recommended power supply for LDR300X.V3 passive
Post by: MttBsh on 22 Dec 2020, 02:11 am
On the Tortuga website the PS12B Battery Power Supply is listed as Out of Stock which I read to mean discontinued.
Title: Re: Recommended power supply for LDR300X.V3 passive
Post by: tortugaranger on 22 Dec 2020, 02:17 pm
On the Tortuga website the PS12B Battery Power Supply is listed as Out of Stock which I read to mean discontinued.

Yes, when we mark something as Out of Stock it's synonymous with Out of Production and is categorized as a legacy product. It explicitly states that the product is out of production is the summary description of the product.

The PS12B Battery Power Supply is something we offered for a while since it was an obvious benefit to our earlier V2 models which fed the incoming power directly to op amps in the LDR control circuit. Starting with the V25 and now the V3 it's difficult to rationalize (from an engineering perspective) how an ultra-quiet power supply will benefit performance since the very first thing this pristine DC power encounters inside the preamp is a switch mode DC-DC regulator running at a few 100k Hz. We've not tested this definitively. Ultimately, the PS12B was not a primary product so it was discontinued.