08-04-2018, 01:41 PM
Interesting topic.
I read the John Swenson thread and then tried to replicate his settings on my RPi3/Allo Boss (older version)/moOde 3.84 setup.
The Allo Boss DAC is based on TI PCM5122. I'm still running the DAC powered from the Pi, but am using a power bank to supply the 5V DC instead of straight from an SMPS.
I'd been listening quite happily with SoX disabled and the DAC set to perform the upsampling to 24bit/192kHz. I'd tried higher bit depths/sample rates, but they didn't seem to make a noticeable difference. Then I saw this thread and its link to John Swensen's posts, so I thought I'd experiment a little.
In the moOde Audio Configuration settings, you can turn off the internal digital filters of the DAC, so I did. (Nice feature!)
To compensate, I enabled SoX upsampling, setting it to 32bit/384kHz. (Too bad it can't automatically upsample to 352.8kHz for 44.1kHz/88.2kHz source files and 384kHz for 48kHz/96kHz source files.)
I'm pretty sure I hear a difference between the two choices of setting the DAC to upsample with Medium Quality interpolation and 24bit/192kHz as opposed to DAC internal filters off and SoX doing the upsampling to 32bit/384kHz. The differences are more about how I 'feel' while listening to music at these settings, about the 'texture' of instruments and voices presented. All very subjective, so apply your skepticism here. I don't hear one option as obviously 'better' than the other. But differences there are.
What I (think I) hear is with the DAC doing the upsampling and SoX disabled, the sound is somehow brighter (not in a frequency response way, though), or maybe a bit more aggressive somehow. Things sound a bit sharper than...
When I disable the DAC's internal filters and use SoX instead. Now the sound is most definitely 'softer,' although high frequency sounds are just as loud (orchestral triangles, the high harmonics of cymbals, raspy/buzzy 'bite' of trombones and trumpets, bowing of stringed instruments, attack of piano notes, etc.). It's the 'texture' that's different. I like this, it feels more 'relaxed' to me, but I wonder which is the more 'correct' presentation of the original audio. I don't know.
I listened to a modern digital recording of jazz group with both acoustic and electric instruments (Ahmad Jamal "Digital Works") and a couple of orchestral recordings, one an analog master (1970s Deutsche Grammophon), the other a 2000s DSD master to CD (Telarc). The differences held through for all recordings.
I'm thinking this might be a taste thing more than an objectively provable 'this is better than that' sort of thing. Has anybody else tried this with their setups?
--
I read the John Swenson thread and then tried to replicate his settings on my RPi3/Allo Boss (older version)/moOde 3.84 setup.
The Allo Boss DAC is based on TI PCM5122. I'm still running the DAC powered from the Pi, but am using a power bank to supply the 5V DC instead of straight from an SMPS.
I'd been listening quite happily with SoX disabled and the DAC set to perform the upsampling to 24bit/192kHz. I'd tried higher bit depths/sample rates, but they didn't seem to make a noticeable difference. Then I saw this thread and its link to John Swensen's posts, so I thought I'd experiment a little.
In the moOde Audio Configuration settings, you can turn off the internal digital filters of the DAC, so I did. (Nice feature!)
To compensate, I enabled SoX upsampling, setting it to 32bit/384kHz. (Too bad it can't automatically upsample to 352.8kHz for 44.1kHz/88.2kHz source files and 384kHz for 48kHz/96kHz source files.)
I'm pretty sure I hear a difference between the two choices of setting the DAC to upsample with Medium Quality interpolation and 24bit/192kHz as opposed to DAC internal filters off and SoX doing the upsampling to 32bit/384kHz. The differences are more about how I 'feel' while listening to music at these settings, about the 'texture' of instruments and voices presented. All very subjective, so apply your skepticism here. I don't hear one option as obviously 'better' than the other. But differences there are.
What I (think I) hear is with the DAC doing the upsampling and SoX disabled, the sound is somehow brighter (not in a frequency response way, though), or maybe a bit more aggressive somehow. Things sound a bit sharper than...
When I disable the DAC's internal filters and use SoX instead. Now the sound is most definitely 'softer,' although high frequency sounds are just as loud (orchestral triangles, the high harmonics of cymbals, raspy/buzzy 'bite' of trombones and trumpets, bowing of stringed instruments, attack of piano notes, etc.). It's the 'texture' that's different. I like this, it feels more 'relaxed' to me, but I wonder which is the more 'correct' presentation of the original audio. I don't know.
I listened to a modern digital recording of jazz group with both acoustic and electric instruments (Ahmad Jamal "Digital Works") and a couple of orchestral recordings, one an analog master (1970s Deutsche Grammophon), the other a 2000s DSD master to CD (Telarc). The differences held through for all recordings.
I'm thinking this might be a taste thing more than an objectively provable 'this is better than that' sort of thing. Has anybody else tried this with their setups?
--
