Do you have a can of freeze spray handy, or duster can?
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I was thinking the same thing. Heat is our enemy.
Well I ask because we want to see if we can locate a cold or bad solder connection.
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Yeah, sorry, that’s what I meant. That’s what I get for replying while walking!
Now sitting a responsibly responding 
Nope, but will get me one and do the test.
I want to thank everyone on this forum who has done the modification using electrolytic capacitors (8 pcs 47uF Vocm and 3pcs 470uF).
I’m so happy i did the modifcation myself.
It is immediately audible.
Increase in tranquility and ease
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Yes, the Vocm mod makes a large improvement 
Turbo
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Hi Turbotk,
Do you use the fixed volume setting in your “DSD”?
And what level did you set it to?
I set it to 92 fixed vol, as I saw that recommended somewhere.
I’d be happy to also use it to drive an amp directly using the digital volume. And have done so on a few occasions. But I have some preamp project(s) going as well (seems never ending so use it with a preamp mostly lately.
Built up the new CLC filter on one channel so far this evening and am having a listen. Will do some testing on that channel and see how it looks and proceed accordingly.
Update- my first look at the new filter so far. Audio band step response looks ok to me, thankfully. Didn’t want to see any craziness/overshoot/undershoot there.
However there are some issues that need tuning; specifically there’s too much 20KHz rolloff with it currently (a little more than 1dB). The simulation showed about half that. I’ll try and fix it.
But meanwhile it sounds good though
Turbo
441Hz 352K8 square wave per Ted’s suggestion (single ended out):
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On a related, hopefully interesting note. Today I also did some work on an Altmann BYOB DAC I have. Unfortunately I broke the original chip in it when I removed it. Sigh. I was going to try a TDA1545 until I figured out finally they are not even I2S (lol- Doh!).
But anyway, DIP socketed it and put in a new TDA1543 (NOS genuine). The sound was disappointing compared to how it was, which was also somewhat of a low noise clarity reference somehow. Hmm… Maybe it has to do with the magic treatment sauce applied to the original chip?
So, got out the 3M stuff and applied to the DAC chip, Ok, a little better. Then I applied to the custom receiver chip, and got slap happy and applied to the 3 crystal osc as well. Ok now it seems to be progressing. But still not smiling.
To the point here, then I applied the BYOB DAC version of the Vocm mod to the TDA1543 Vref, which is also used to drive the OA In+ legs. SO they better be dead quiet through the storm, it seems to me.
Ok, now I went from ~ meh to smiling again. It transformed it. That thing was making some music while I worked on the DS today Lets not let that cat out of the bag to the TDAxx crowd yet
Turbo
I asked in Munich, they said they are compatible
Well if you’re willing to fly wire it you can make a lot of things work in there. A mu metal core will bring a step up in see-through clarity. I used a Sowter mu metal core. Then amorphous core LL1674, now amorphous with pure Cu windings.
Turbo
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T, I still think the transformer is LimFac in the analog performance. If you run a multi-tone test you will see that core saturation really makes the low frequency distortion pretty bad. Above a few hundred Hz its quite good though. The Lund / Sowter stuff is quite good but very expensive.
Guys, I was really excited about this upgrade in the capacitors that colleagues have been doing, but I saw that we tried different types and brands of capacitors.
I would like to ask what the best combination is, if there is a consensus on this, I understand very little about Electronics but I have a great local Technician who will do the job perfectly and I would like to have the project ready just for him to implement.
Thank you all for the excellent reports and experimentation with our Bravo DS, this topic is unique in the audio community!!!
I bought the
- UES1C470MPM: 47uF 16V Nichicon ES type
- UKZ1E221MHM: 220uF 25V Nichicon KZ type
Both types are audio cap’s
And recommended in this topic by “Turbotk” & “Lufubu”
I didn’t try others but i like Nichicon in most situations.
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Yes, I would use the 47uF Nichicon UES (Muse green colored BP bi-polar). Use anywhere from 10v-16v for small size (lower voltage = smaller size). I used 16v because I happened to have them already. Doing over again I’d likely use 10v.
Eg: https://www.digikey.com/en/products/detail/nichicon/UES1A470MEM1TD/4317390
Have the installer put the “negative” lead (the short lead) on the low impedance side, eg the side of the resistor opposite to the Vocm output.
You could go larger uF, up to say 100uF, but I would not go smaller than 47uF. We do know 47uF works well.
We have no science formula for this application, just instinct. We have to keep the size reasonable as well. And the Muse BP isn’t magically the only one that will work here, just a known good quality cap for audio applications. If cost was no object I would possibly reach for Kaisai BP for this (if the size was also right).
Turbo
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Just for grins Oh my, memories Well, we all have to start somewhere right? What a project this was- TDA1543 NOS based DAC. Prototype work. ~ 2013.
I just dove in basically, figuring there was no better way to learn. That large green board on top of the stack was a hybrid PLL Clock Cleaner (Femto seconds) eval board from local SiLabs (thanks guys). It dropped measured CLK jitter from ~ 80ps from the SPDIF receiver down to < 2ps (the tool res limit). Yes, it was audible.
At the time of the image it had passive LPF out with some wild parts. It started with passive i/v as well, but was working on a CB circuit for it. At the time I knew ~ nothing about how to linearize open loop analog circuits, etc. Part of the schooling and hands on learning process(!) A steep learning curve it is too, whew.
Sharp eyes might spot a smallish proto board peering out at the top of the lower device pile with some old discrete logic on it. That was part of what I was hoping was some “secret sauce” 
Naivety… Fast forward to now though, I find that Denafrips for example does similar with their NOS- it draws a straight line between sample points rather than an abrupt stair step of traditional NOS. Denafrips does a much better job of it with their huge speed advantage they have than I did with the proto driving 4 discrete DAC chips though, of course I called it “4x hdw upsampling”, but that is open for interpretation It basically just moves the ultrasonics around a bit, which can be a good thing as well.
At the top was a friends design (commercial). Think I was having a listening throw-down comparo there.
I’ll share something here as well… I guess it’s ok. Was always dabbling in high end audio but the main reason I became so over the top passionate about the sound in ~ 2012 was, I suffered a hearing loss episode in 2010. Was suddenly 100% deaf in one ear, literally overnight. That shook my world, needless to say.
I was fortunate to get much of it back though (thank God), and afterwards that triggered the huge deep dive into sound which continues today. Perhaps it was a divine wake up call.
I consider it similar to someone who dabbles in painting; then one day they are struck blind. Then over 6 mo or so they get much sight back. They might then start painting masterpieces (or trying to their ability at least
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That’s awesome.
You’re too kind sir