Hello all,
I’ve just come back from holiday and I can take some time to write my test.
First of all, As I’m blind, I was able to carry out double-blind tests. And that’s no joke. In any case, it’s a very interesting experience. In my various tests, I’m sure that if I knew what I was listening to, I would have preferred the more expensive solution!
The aim of this test is to compare the USB A output of my Lenovo X1 carbon with a pure high-end streamer like a Lumin U2. In all cases, Audirvana is the starting point for the audio stream.
I tested two DACs: McIntosh MA5200 and LAIV Harmony DAC.
Points that don’t vary during testing:
- Audirvana studio under Windows 11
- the Lumin U2 is connected to Audirvana using the UPnp protocol. (no problem here)
- No oversampling.
- My speakers are Cabasse IROISE 3 connected with audioquest 4 cond spirale solid LGC Type 2 cables.
- My amp / preamp is a McIntosh MA5200
Test 1: DAC integrated into the McIntosh
a. Audirvana → USB DAC
b. Audirvana → UPnP Lumin U2 → Coax DAC McIntosh
Here it was very easy to see a difference. If I had to say only one thing, it would be that the stage width is very much narrower with the USB input. I didn’t continue the test for long with such differences.
Test 2: LAIV Harmony DAC
a. Audirvana → USB Harmony → RCA McIntosh
b. Audirvana → UPnP Lumin U2 → Coax DAC Harmony → RCA McIntosh
Here, still double-blind, the trial lasted longer.
There were differences in the soundstage, but they were much less obvious. I’m not a specialist at putting my acoustic feelings into words, but in any case it was easy to hear a difference in quality that wasn’t down to accoustic preference.
The Lumin U2 was always a step above.
I was glad to do this test because a month ago, I didn’t think that there could be acoustic differences in the digital domain.
I’m convinced that there are almost never any digital errors in the digital audio signal.
But I think that the differences in quality are due to the clock that is sent with the digital audio signal and the noise that can propagate through the cable.
I’d like to know how the clocks synchronize between devices , but the info isn’t easy to find.
There may be solutions to rework the USB output of a laptop, that might be a good idea.