I have a problem, I not understand. I read all my music from my hard disc. It is attached to my small Acer computer. All is read without problems, no drop outs connecting it through USB.
BUT, I put the harddisc on my OPPO 93, which is not so audiophile as the 95 and newer models. But connected through cinch on the Gustard, the sound is better then from computer. I cannot understand that through usb, with bytes, 0 and 1 it can sound and be different then connecting by cinch.
When I play from usb, sound is very transparent, staging is very good. But it sounds sometimes a bit too thin, and more digital. With connection through the Oppo, on first listening it is not that different. But the longer you listen, it is obvious that the sound has more grip in bass, sound more live (usb thinner bass and less 3d), and I have less digital edge, sound just slightly warmer, that makes you feel more involved. Feeling more "being there", when with usb it feels like I have electrostatic speakers instead of my B&W 800 D.
Not understand this, how is this possible. Somebody an explanation?
You might be having problems with RF noise contamination coming from the computer, the symptom being the sound thinning out with the loss of bass extension. If you have a SPDIF connection on the computer give that a try, this is becoming less common as time goes on.
SPDIF on the Gustard is isolated via the Pulse transformers, you can see them right next to the SPDIF inputs if you open the top cover, this greatly reduces the RF noise coming into the DAC.
Injecting RF noise into the 9028 affects its ability to perform the digital to analog conversion.
Isolating the USB input externally is relatively costly, devices such as the Uptone ISO Regen is about 30% of the X20's cost.
You are correct on the point that the data streams being 1's and 0's however both USB and SPDIF are serial interfaces, there are 2 streams, audio data and the clock data combined into 1 physical stream.
This has to be separated at the receiver, the ability of which determines the final sound quality, clock recovery is particularly important as it determines the jitter of the signal feeding the DAC chip (9028).
The lower the jitter the less work the 9028 has to do to clean it up.
SPDIF came out in the late 1970s, USB 2.0 asynch mode in the late 2000's, the intervening 30 years has allowed for improvements in areas such as clock recovery than is mandated in order to meet the USB 2.0 spec, the makes the requirements quite lax in relative terms for SPDIF so most manufacturers to not spend the time to make SPDIF better, and you were able to pick out the sound quality differences.
This problem of SPDIF sounding better than USB is not unique to Gustard, Schiit recently introduced their Gen V USB input card for their DACS which provided RF isolation after numerous complaints which included their top of the line R2R Yggdrasil dac. The new card fixed most of the sound difference issues and finally allowed the performance potential of USB to be realized.
