HOLO Audio Spring DAC - R2R DSD512

[axle_69]

Some people preferred the basic level Spring in NOS mode compared to other reference DACs and the inverse in OS mode, and most agree the Spring sounds best in NOS mode. Do you know if the Spring has an analog low-pass (reconstruction filter), and what type of filter it is (curious if it is a sharp filter between 20 and 22.05 with ripples or something more gentle that would work well if upsampling in the computer)?

I don't care much about DSD, and would probably not use OS. Many may think the same. In that case wouldn't it be better to transfer the cost of something that a lot of people may not use to a better USB implementation? Or remove the USB completely and sell it as a separate module...

[axle_69]

Thanks for the reply. I was asking about the analogue filter. If it was designed as a NOS DAC normally it would be a filterless DAC or have a relatively sharp filter. From your reply it seems to have an analogue filter with a gentle slope (probably designed for upsampling in the DAC or in the computer), that works well with high res files or upsampling in the computer. This brings another issue in my case, 176.4, 192, 352.8, 384 would have to go through USB, and if the USB implementation in the DAC isn't good enough that is another can of worms.

[axle_69]

"(not sure why, myself and others love it, given enough care with the input stream)".

Exactly because of that, USB output directly from the computer to the DAC depends a lot on what the USB board in the DAC does.

[axle_69]

I didn't say I had. Trying to make a decision between the Spring and another DAC. It seems some people feel the need to put something like the Singxer SU-1 DDC in the middle. In the case of the other DAC it would be computer without upsampling > Toslink up to 96 > upsampling in the other DAC, whereas in the case of the Spring it would have to be upsampling in the computer > USB > ? > Spring. The Spring may take the lead on the DAC itself, the other DAC will take the lead on the upsampling algorithm (probably even compared with upsampling in the computer), but what happens in the middle is important as well. I could upsample 44.1 to 88.2 and use Toslink with the Spring but my guess is that the analogue low pass has a gentle slope and a higher sampling rate will be better. So it ends up being a question about upsampling algorithms and digital connections as well. How does the USB input (with output directly from the computer) compares with the others?