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New digital PS designed by Salas

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MisterRogers:
Wanted to be sure you all knew about a new PS design that Salas has made available. I've build a few and installed them in two DAC's. In both cases they replaced BIB's / LDO's. The improvement was astounding. More detail, more organic, more weight, increased separation. I suggest you builders check it out!


http://www.diyaudio.com/forums/group-buys/258340-gb-salas-reflektor-d-power-supply-digital.html

MisterRogers:
One of the DAC's I installed this PS in was my 'FrankenDAC' (BIII, PH shunts, Amanero, reclocker, clock board, discrete low noise power for clocks & output flip flops, XO Caps, etc.). Sabre chips have always revealed the detail in music, but getting rid of the 'edge' or digitalis has been a continual effort with FrankenDAC. This PS - one feeding the DAC and another feeding the clocks has the 9018 sounding more like an AK chip then ever.

Peef:
I hope this doesn't sound terribly silly, but why would it be especially well suited for digital? The shunt mosfet's impedance is going to be hard to keep low in the higher frequencies because of the gate capacitance requiring more drive than the mirror can provide. Looks great for the audio band though. I'd expect a BJT or cascode to work a bit better for high frequencies but can't get it to sim right.

MisterRogers:
I posted your question to Salas - wanted to hear for my self his response:

"If it tells something to him its low on 1/F noise, has 160uV RMS 20MHZ wide band noise, its flat output impedance goes up 3dB not before 280kHz. LM317 does that at 1KHZ for instance.

*Reflektor-D means a Reflektor version suited for digital voltage range BTW."

Solderdude:
It does not matter what the shunt does at higher frequencies (whether it is still active as in having a low resistance) because noise on the digital chips isn't determined by the shunts ability to 'shunt' those frequencies, but is solely determined by proper decoupling as close as possible to the chip(s) in question.
It is physically too far away from it anyway as the PCB traces have too much inductance for a low impedance power supply to be of help.
Certainly when that shunt PCB is connected with a few cm of wires  ;)
The noise in the HF range can cause problems with complying to (common mode) emission regulations and/or have other strange interference effects.
Layout and PROPER decoupling are paramount here.

Low noise in the 'audible range' and above is what some claim that counts as it is these lower frequencies that 'modulate' the clock and PS lines of the associated chips (think H-L transition points and references) is what causes the sound to 'degrade'.

It should be noted that from a technical point of view it is hard to prove the claims of the audibility of it but that's another matter entirely which I won't go into because I may be commandeered to  walk the plank   :)p13

In any case, a good low noise power supply never hurt any circuit and if it brings something good to peoples ears (not necessarily mine) I am all for it.

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