PSAudio P300 mods with photos

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I've been working on this P300 for a time now. It's finally working but not sure it's finished. I may still have some things to iron out. I hope to use this thread to ask questions on things I don't quite have solid understanding of.

for most part I used 3 ALW/Jung regs to supply MW2 card: +/-14V for AD8599 opamps and voltage reference; 5V for AD7392 DAC and digital stuff, but I also put in nearly every component in the PSAudio PCBs to work on soldering skills with MetCal iron. All is probably overkill but I learned a lot just by making/rebuilding the circuits. onlinemetals.com cut copper pieces and I'm waiting for copper/aluminum plates to cover remaining open spaces:

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


I used Walt Jung's "Build an Ultra Low Noise Reference" for voltage reference for AD7392. I should have twisted those wires more tightly!:

An externally hosted image should be here but it was not working when we last tested it.


ALW/Jung +5V reg:

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


ALW/Jung -14V reg:

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


separate digital supply and also Nicicon VL 3300uF filter caps for amp. I wanted to use BC Component caps but they were too large 30-35mm diameter (had to be 25mm) and expensive..those Nicicon 100V were about the only I could find that would fit:

An externally hosted image should be here but it was not working when we last tested it.


the output wiring is from a nordost vishnu power cable. I decided to shield it, not far enough up cable!:

An externally hosted image should be here but it was not working when we last tested it.


I apologize if size of photos caused any problems.
 
i removed plastic from caps because I think they look cooler without them. I cannot comment on the sound which is better with/without. I don't know.

messy.. you make my heart cry!
here you can have what this p300 was a few years ago..it doesn't sound as good! : p

An externally hosted image should be here but it was not working when we last tested it.


with space provided there wern't a lot of options if I wanted to use the 3 alw/jung regs..I had never built them before and wanted to try them. Is that a cop-out statement?

i didn't rebuild this to sell to anyone or provide service to others who have one, more to learn, experiment, and hopefully end up with something I like and want to listen to. Is that a cop-out statement?

maybe it is a bit messy. sorry you don't like it.
 
i really dont know

what exactly was this device before you give it that look and that mess ( sorry thats just a personal opinion i would never do a thing like that ....at least not in this way )

as about your question if caps sound better with or without the plastic i dont even bother to think about it .... you should do the same ........

please dont missunderstand my opinion ....we may have diferent ways of thinking as about improovements ....
 
mw2 gnd connections with +/-14V regs

here is crude diagram of grounding of PS Audio MultiWave 2 with ALW/Jung +/-14V regs. I have question regarding grounding of center taps of transformers in diagram. windings are from the 2 separate transformers that came in PSAudio P300. Original circuit had CT GND connections meeting at 2 1000muF caps, and 317T/337 load gnds, coming off voltage set resistor (in 317T/337 circuit)--the load gnd, the one 317T datasheet advises to connect at load and not psu for best regulation--these (317/337 LGNDs) met there too, at 1000muF psu caps. This 'psu gnd' was then connected to 'MW2 signal gnd' via one long PCB trace. All this maybe because regulation of opamp power rails was not priority because of 100db PSRR of NE5532 opamp? Anyway, I felt I had to separate the center tap gnds from meeting at 1000muF psu caps because this would make a gnd loop when load gnds of ALW/Jung regs met at opamp signal gnd. Diagram shows exactly how I connected UNreg psu, ALW +/-14V regs, and 2 of the opamps they power. Does all seem okay?


I don't know electronics well enough and have trouble visualizing current loops running through force and gnd traces. Both ALW regs draw 100mA of current. Is this current drawn from the CT GND of transformers or the ends of secondary windings? Does it flow out from ends of windings and back to CT gnd? By connecting CT GND to the 1000muF cap, does the 100mA current loop close/end at that cap? at the ALW reg? at the opamp signal gnd? If I were to connect CT GNDs at opamp signal gnd star point instead of 1000muF psu caps, would this force 200mA of current through that star point, causing troubles, or does the 200mA flow through there anyway? I really know nothing.


diagram could be bad/crude enough that no one will look or take seriously.

An externally hosted image should be here but it was not working when we last tested it.
 
I don't know why I changed position of C5, decoupling cap for logic IC on right. The original position, equal lead length for V+ and GND, is just as good if not better. Total current loop length is close to same either way. Current loops in decoupling caps for AD7392 on right, V+ to GND (red cap), Vref to GND (silver cap), are quite a bit tighter now though.

An externally hosted image should be here but it was not working when we last tested it.
 
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