I have the Gustard X20 but figured it did some converting to PCM for the volume control

So if one wanted the best DSD DAC (no conversion to PCM), what choices are there? Note that I don’t care about having streaming or built-in headphone amp.

How is this compared to the U16? I have an offer to get a used U16 for under $250 (still close to original sales price), but am wondering if it’s worth saving up for the U18. I have a Gustard X20 DAC That I’ll be using with it.

Can someone confirm this will work without problems with my X20. Thanks!

If you don’t want the U16 after your upgrade let me know :)

So is this even worth getting? I have a Gustard X20 and would like to try DSD512. Would there be sonic benefits to adding the U16 or is it too unstable?

Anyone have a Gustard U16 DDC they're willing to part with?

I have the Gustard X20 and am running DSD256 from J.River and it sounds great. What would I be getting by adding the Singxer and outputting DSD512?

Gustard was very good at dealing with a repair of my X20, which was under warranty. They sent me two entire PC boards from the unit, free of cost, from China to troubleshoot.

Has the firmware been made available for the SU-1 to enable DSD516?I heard they've been working on it.

Got the ifi iDefender 3.0. Works perfectly! Problem solved.

Yeah, that's the one I had. I tried between a phono pre and amp and it was dreadful. Might not be bad in this case. I've got a USB isolator on order. If that doesn't work I'll just use the cheater plug and be done with it.   Thanks for your help!!

Thanks. The first option is a bit expensive. The second I have used in other situations, and it kills the sound (depletes the bass), so that's out of the question. The third option looks good, though the USB isolator is a tad cheaper, so I'll try that first.   If I were to leave the amp...

Ungrounding the amp. That's it.   I would prefer to leave it grounded, but don't know what USB ground isolators will work with DSD. I'm eyeing the ifi iDefender.

So what's the safest way to set this up? Running a wire from the tab on the 3-to-2 plug to the PC case and from the PC case to the amp ground/chassis?

This scares me: https://en.wikipedia.org/wiki/Cheater_plug#Safety   What are my other options? I'm assuming grounding the USB isn't possible without getting one of those devices that limits the frequency of audio files.

So I'm told it is absolutely not safe to unground the amp. What to do now?!

SOLVED IT!! I just went back to the system just now and it was dead quiet. How'd that happen?? I don't know. So I started unplugging the grounds. DAC ground out. Still quiet. PC ground out. Still quiet. Amp ground.... aaaand, that's it. I didn't even need to attach the ground to anything...

What do you mean by "leave the other wires in place"? I have tried grounding the PC to the amp chassis. Then I added the amp and DAC grounding wires, running to the PC. If I ground only the DAC that would mean disconnecting the ground wires of the others.

OK, I've got the PC, DAC, and amp all plugged into 3-to-2 prong adapters, with the ground wires running as follows: DAC to PC case; PC to amp chassis; amp to PC case.   Same noise.   Could this still be a ground loop issue? I'm starting to doubt it.

Thanks. Just tried it. No difference.

OK, I attached the ground from the PC to the chassis of the amp. Same noise. Will try connecting the DAC and amp grounds next.

No, different make entirely.

Remember that I switched out the power supply on the PC and had the same problem. Anyway, I now have the plugs, so I'll experiment later tonight. Thanks!

OK, will try. 3-prong to 2-prong on PC power supply, with a ground wire running to the amp chassis or ground. Easy enough.   How do explain that I get no noise using my laptop?