Can you explain more about the Filters 1 and 2? Currently I prefer using Filter 2 finding that it sounds more analogue and less forward.
The default filter for DAC 2.0 every time you turn on LIO is FILTER 2, which is the "NOS" filter. This is a non-oversampling, "digital
filter-less" mode. If you feed 44.1kHz in, you get 44.1kHz out. If you feed 192kHz in, you get 192kHz out, etc. And the digital filter in the dac is bypassed and instead there is a minimal analog filter on the Class A output stage. As you mentioned, this is a very detailed natural sounding mode.
FILTER 1 is a "minimal phase, slow roll-off" filter mode that also upsamples all PCM to 768kHz. So no matter if you are playing 44.1, 96, 192, 384, etc... it upsamples to 768kHz and then performs d/a conversion.
NOTE: Both F1 and F2 are only used with PCM music - not
For DSD, I do filtering in the analog output stage.
I read this from roonlabs discussion board:
" .. They (DAC chips including AKM, ESS, Ti etc) almost all upsample PCM to high res DXD PCM rates internally and then convert to a DSD type file before outputting analog."
Does this apply to the AK4497eq chip found in the DAC2.0 and if so what would be the optimal Roon or HQPlayer upsampling frequency to keep the upsampling in Roon or HQPlayer without it being done a second time in the chip before converting to analogue?
This is not
the case for LIO DAC 1.0 or 2.0. No PCM is converted to DSD in either LIO dac module.
If you don't want any upsampling to take place, simple run LIO DAC 2.0 FILTER 2 (default) and set Roon sample rate conversion to "Disable." What you feed in is what you get out.
If you want Roon to sample rate convert all PCM to DSD, set sample rate conversion in Roon to DSD256 or DSD512 (I still find them both to sound nearly identical, and DSD256 uses less processing power). In this case, F1 or F2 makes no difference because you are then feeding DSD to the LIO DAC 2.0.
- Oh by the way, the cracking noice at higher upsampling frequencies may have been caused by older microRendu software. Sonore tend to update their firmware but keep the version numbers the same and so you don't know if there is an update until you try to force the check. I updated from 2.5v to 2.5v (there were many file changes reported) and the cracking noice is mostly gone even at DSD256. Will continue to observe and test more.
It could also be your computer running Roon, or your router (are you going WiFi between your computer and your router)?