ross martin pcm4222 adc hiss at 96k

no i didn't.

i'll give that a try this week and see how it goes. have you had a similar issue?

ok thanks, that's a big help.

I think its amazing Ross advertises PCB designing. His PCBs are cobbled together from adapter boards I'm surprised that half the RMA units even work.

But you can't really "copy" a 4-layer PCB, can you?

This got interesting. Is that standard for audio Svart? Both layers? I'm guessing it's low voltage and you might be able to put it up to the light to see?

I don't think it's standard for most consumer audio, but I'd bet that the pro-caliber stuff is at least 4 layers.  In my day job I MUST use specialized PCB design, and some of the stuff that seems like ridiculous overkill for audio is bare-minimum for high speed work, but it helps keep things clean and tight.  

PCBs don't cost nearly as much as they used to, so having more than 2 layers is not prohibitively expensive anymore.  I think the cost difference between a 2 layer board option and the 4 layer option I went with on my design was only a few dollars.  For super high volume stuff like Behringer, that might mean hundreds of thousands of $$ over the lifetime of a product, but for something that sells a few dozen/hundreds a year, that's nothing if you're gaining performance and reliability.  I'm sure RM has had to repair tons of his units due to the wiring and (IHMO) shoddy assembly.  if I spend more money on a PCB that allowed me to have very little wiring, that's money I saved in the end by not having reliability issues.

What I meant about layers and guessing is that anyone who's concerned about power supply cleanliness would already consider at least using ground planes, and more recently power planes.  Going further and seeing that the outputs of my power supplies use wide top planes that terminate into the board with a half dozen vias would realize that there must be internal layers, as would seeing no connections to the power traces on the back side of the board for the vias that bring the power up locally to the opamps, etc.  That kind of educated guessing is what I'm talking about.

On mine, I used ground fill around all the parts and audio/data traces on the top and bottom.  The 2nd layer was ground under all the signals and power but also some control lines and such routed away from the digital streams and analog audio traces.  3rd layer was power planes to keep all supply conductors as low impedance as possible to reduce the amount of local decoupling necessary, and to reduce parasitic inrush currents (that happen having large caps far away from the supplies).

Awesome. Thanks.

i have both the rm pcm4222 and svart's adc/dac.
i haven't used anything but svart's box for critical listening since comparing it to everything else i had (bla sig modded 002, ross martin, motu 16a).
i've been buying gear and building up a studio regularly for the last 5 years and i've noticed that purchases fall into two categories: the things you buy once that get used every day, and then everything else that leaves you chasing.
svart's box was a piece of the chain i didn't have to think about anymore because i felt i had solved it.