charleski
100+ Head-Fier
- Joined
- Nov 10, 2014
- Posts
- 385
- Likes
- 374
If I'm reading the posts correctly, in his first test he down-sampled the 24/96 original to 16/44 with foobar, but didn't then up-sample that back to 24/96. But then went back and used dbPoweramp to down-sample and then up-sample for the second. Is that correct?
There's another question lurking here which might be a bit more interesting than the old 'Can I hear a difference with hires' chestnut. And that's whether the DAC produces audible differences when fed with hires vs std signals. The Modi 2 uses an AK4396 DAC which, like most modern DACs, upsamples everything through an interpolation filter before feeding it to a ΔΣ D/A block. As seems to be the fashion, the AK4396 allows the low-pass filter used in this process to be switched between fast and slow roll-off. While Schiit seem to be a little secretive about the filter choices they make it seems possible they set this up for slow rolloff, which runs the risk of introducing IM from aliased images when fed with 44.1kHz signals, but will be operating far beyond the audible band on 96kHz ones. On a track with a lot of high-frequency material like the one used, this might be a factor. Maybe.
There's another question lurking here which might be a bit more interesting than the old 'Can I hear a difference with hires' chestnut. And that's whether the DAC produces audible differences when fed with hires vs std signals. The Modi 2 uses an AK4396 DAC which, like most modern DACs, upsamples everything through an interpolation filter before feeding it to a ΔΣ D/A block. As seems to be the fashion, the AK4396 allows the low-pass filter used in this process to be switched between fast and slow roll-off. While Schiit seem to be a little secretive about the filter choices they make it seems possible they set this up for slow rolloff, which runs the risk of introducing IM from aliased images when fed with 44.1kHz signals, but will be operating far beyond the audible band on 96kHz ones. On a track with a lot of high-frequency material like the one used, this might be a factor. Maybe.