AES/EBU sounding really, really nice with this DAC. USB a little more fatiguing... from my crappy old laptop core
Roon -> Bryston BDP2 -> Lampi (nearly) GG3 -> ARC Ref5se preamp -> ARC Ref75se amp -> Harbeth 40.2. Cables are all custom made from Signal Cable - not exotic but good quality to my estimation.
Glad you found a (temporary) solution.
The "crappy old laptop" is your USB problem. Laptops are not designed as music servers, they are actually the worst possible source, and have terrible electrical noise and jitter, as you are finding out. The USB filters I disparage are made as a band-aid to hide the problem but they don't solve it. Your Lampi deserves better.
I don't understand how Roon can be presenting 128 or 256 DSD from my crappy old laptop core, when I understand that HQPlayer needs some beefy compute resources to do the same thing better.... if they are even doing the same thing....).
HQPlayer's developer Jussi Laako has answered your question in
HQPlayer Audiophile Style forum:
"Because you can reach the same goal in many ways, if you just want "DSD1024" [or DSD256] and are not picky about actual quality.
"You can do it easily if you lower the quality bar and consider something "good enough". DAC chips do similar thing these days too. So the usual approach, like DAC chips do is to first have some platform (FPGA or on-chip DSP) and then make processing that can run on that what ever limited amount of resources you have. For example DAC chips run proper digital filter up to 8x rate and they they just repeat the same sample value 128 times to make up 1024 "rate" for the modulator. Or some more fancy chip like Chord DAC FPGA runs digital filter to 16x rate and then does linear interpolation (argh) to 2048 "rate".
"While I prefer to do things vice versa, first make specifications of what I consider "perfect" result and then make processing that reaches the wanted quality level and runs as fast as possible. And then you need to buy hardware that can run it. I don't tailor the algorithm to run on any specific hardware, the hardware needs to be tailored to run the algorithm.
"For Chord's million taps to 256x which is best they can do now, you can run 16 million taps on cheap GTX 1060 GPU to 512x in comparison... (and it's less than 25% load on that GPU) Like the number of taps alone would matter in first place...
"Most FPGA's do processing in fixed point and at lower resolution. I do processing in 64/80-bit floating point. Making an FPGA do complex floating point processing already takes immense amount of FPGA space. And I would never resort to something like repeating samples or linear interpolation to reach the target rate."
