Hi Bob,
I have several DIY amps including a F5, AlephJ, SKA, and never had any hum issues. I ground the amp PSU to the IEC ground through two reversed diodes and a 10R resistor in parralel. The amp boards are grounded to the PSU boards. I'm still waiting on parts to get around to my V3 build.
PJN
I have several DIY amps including a F5, AlephJ, SKA, and never had any hum issues. I ground the amp PSU to the IEC ground through two reversed diodes and a 10R resistor in parralel. The amp boards are grounded to the PSU boards. I'm still waiting on parts to get around to my V3 build.
PJN
Thanks PJN. I posted on one of the Pass threads this morning and got some interesting answers. I'll give them all a try.
One more finished. My first SMD project and managed not to burn anything!
Of course soldering not so nice as others here, but it works.
Initially I thought I made a mistake or burned something, as I had the right voltages but no sound, but I only had to reflow some joints on Q2 and Q1.
Info here helped a lot.
Power supply regulator is a Salas reflector.
Sounding really nice right now!
Of course soldering not so nice as others here, but it works.
Initially I thought I made a mistake or burned something, as I had the right voltages but no sound, but I only had to reflow some joints on Q2 and Q1.
Info here helped a lot.
Power supply regulator is a Salas reflector.
Sounding really nice right now!
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If anyone is interested, there was a problem with the grounding of the Pass BA-3 amp. Fortunately another member had sorted it out and gave direction. A seperate problem totally unrelated to the V3 did develop but was also resolved.
You can read about it starting here and follow through to today's post if you think a V3-Pass combo is in your plans.
You can read about it starting here and follow through to today's post if you think a V3-Pass combo is in your plans.
Correct. The other major change was putting all the grounds on the same star ground/bus. That was close to what I had but the two channels were done seperately (individual stars) without a unique connection back to earth. Still have the one MyRef to get hum free, and I suspect that will also center around a CL-60.
Just a note - Subbu/JP DAC sounding simply excellent with the definitively clean Pass amp. Working well together for about 3 hours. The lower mids are tight with the bottom being deep and well damped. There could be a little more top end shimmer, but I'm looking forward to the upcoming V3 cap upgrades to dial that in. But the stock build sounds really, really good to these ears. 🙂
On the subject of grounding, what is recommended for the DAC? Just connect the mains ground to the chassis?
I'm not recommending this for anyone on a safety basis - but I installed a two wire set on the current platform. I will most likely do the same for the final chassis that will essentially be double insulated - some use of wood/Plexiglas.
(As shown still needs heat shrink at receptacle.)
(As shown still needs heat shrink at receptacle.)
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the suggested parts for C17 is now 1uf ceramic. Is there any ill effect if I put a 2uf for C17, I happen to have some lying around.
C21 suggested with 470uf polymer, would it be also good - sound wise - to put tantalum there in same value ?
C21 suggested with 470uf polymer, would it be also good - sound wise - to put tantalum there in same value ?
I think 2uf is also fine for c17. Regarding C21 i think the choice is a matter of taste. JP recommended Vishay, some others found polymer sounding better, my choice was a 220uf BG PK. You are free to find your caps to your taste.
atupi,
the // oscon SEPC or polymer Nichicon FA (the red on top) with a BG NX (the red one) give me outstanding result in another DAC
the // oscon SEPC or polymer Nichicon FA (the red on top) with a BG NX (the red one) give me outstanding result in another DAC
the Santa capacitor, like the red Baron, red pcb, red cars: it sounds better.
2 red caps are even better, it's the R2R sound !
2 red caps are even better, it's the R2R sound !
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I used an OKI PS-900 and 1,8mm chisel tip.
Difficult to solder was the regulators an Q2, were I had to use a JBC 15Watt with a very fine tip, in order to flow the solder. One solder point the time, while blowing and then wait the chip to cool down, in order to continue.
I also used a flux pen.
Magnifying glass of course and check every soldering point.