Just picked up a used Schiit Modi 3E dac and was fooling around with it. This dac is amazing and for sure it does not support native DSD nor MQA files.
Just for my curiosity, I wanted to find out how it would handle a native dsd and mqa file. Surprise!, it plays pretty well. The screen on my computer and peppy meter screen show dsd and mqa format.
Playback set up: DSD Direct, Mixer Type - None
However, when I chose DSD over PCM and plays a DSD file, I got nothing but hiss sound.
I really don’t understand. Can someone help me explain?
HW: RPi5/8gb
SW: Volumio (beta) 3.766
Dac: Schiit Modi 3E
If your DAC does not support Direct DSD (or the resolution at which you’re playing them) it will automatically convert DSD to PCM
“it” refers to the MPD software in Volumio. In Direct DSD mode, Volumio will do a conversion and send a PCM stream to the Modi 3E.
The Modi 3E also does not support the DSD over PCM (DoP) data format. When played like a normal PCM stream, DSD over PCM data is designed to sound like hiss. See this: DSD over PCM (DoP) – Wikipedia
A DoP stream is designed to sound like low-volume noise when played back by a PCM-only DAC, while a DoP-capable DAC will detect the presence of DSD data, extract it from the PCM and play it back as DSD.
MQA files are FLAC files that can be played like normal FLAC files. A typical case is an MQA file formatted as a 48kHz/24-bit FLAC file. Without MQA decoding, it will play like a normal 48/24 FLAC file. However, the low 8 bits of each 24 bit sample actually contain MQA encoded data. For example, an MQA decoder can use the encoded bits to perform the first “unfold” to produce 96/24 PCM. Subsequent unfolds can produce a stream as high as 352/24, if the audio was originally was recorded at that resolution. There was a lot of skepticism in the audio community about how it could be saved into a 48/24 FLAC. MQA Ltd refused to provide technical details to support their claims, and subsequently many consider MQA to be a marketing scam to extract licensing fees.