Hi, received my D90 MQA and enjoying it immensely. I want to see if I can use the I2S input as that was one of my reasons for purchasing the unit. I had previously thought I can use my Pi4 I2S output as input for the DAC, but that appears to be not correct. Therefore, I googled what else I can use and the Singxer SU-6 came up. It’s quite pricey so I wanted to see 1) if others have successfully use with with the D90, 2) can I use DSD512 via I2S from the SU-6 to the D90 and 3) it appears the SU-6 uses the XMOS XU208 while the D90 MQA uses the XU216 chip...as such, will there be an improvement using the SU-6 given the higher spec’ed XU216? I’m thinking the SU-6 will still need to take USB input and convert it to I2S.
Lastly, what happens internally in an USB DAC? Does it convert USB to I2S before processing and it’s just that the SU-6 will do that better or does it skip the I2S step all together? I’m trying to understand why adding a conversion step (eg., adding the SU-6) improves sound quality.
thank you!
Hi
Hammer. Welcome to the forum.
I explain my experience with the topic of USB interfaces and conditioners.
Before having the D90 associated with a fixed form SMSL SP200 and Sennheiser HD800s, I had an NAD M51 and an HDVD800, very happy with its sound, but whose USB input of the M51 was not exactly good (year 2012). I like to experiment, so I tried to use an interface to use the AES / EBU input of the M51, it gave me a good result and since then I have been testing a few devices.
I have come to have a Yellowtec Puc 2, a Gustard U12, a Matrix Spdif2 and a Singxer SU-1, various USB conditioners as well, including an iFi iUSB 3.0, various combinations, low noise power supplies etc. Finally, some with good results and others not so much or none, but always using the AES / EBU entry.
I still have the Matrix Spdif2 and the Singxer SU-1 and contrary to what happened with the NAD M51, I can assure you that I would not be able to distinguish between any of the inputs of the Topping D90, with or without interfaces and including the i2S through the SU-1.
With everything I've tried, it can be said that I would be prejudiced against the D90's USB input, but the opposite has happened to me.
And it is what surprised me about this DAC from the beginning, the good audio quality through a simple USB connection / cable. Sometimes when I connect just the cable, it seems to me like something is missing, out of habit.
What's more, if you had to choose between any of your inputs, you would choose USB. I have the impression, only the impression, that it is marginally better. For a while now, the USB section of the DACs has improved a lot or at least in some. And for me it is fundamental because I always use the PC as a digital source.
In my opinion, if you do it only for the sound, you do not need to buy anything and if you buy it because you need an interface to obtain another type of digital output at the same time, you do not have to worry about the sound either because you will not notice differences. to worst. They all sound good. It is a good DAC as is. At least in my system and with my ear.