DSD vs PCM, and what happens to DSD on a phone

PCM

Pulse-code modulation stores the waveform as numbers: 44,100 or more times a second, each sample a 16- or 24-bit value. CDs, FLAC, WAV, ALAC and nearly all streaming are PCM.

DSD

Direct Stream Digital stores a single bit, 2,822,400 times a second for DSD64 (the SACD rate), twice that for DSD128, four times for DSD256. Each bit says “up” or “down”; the density of ones follows the waveform. The quantisation noise is pushed far above hearing and must be filtered out on playback.

What your DAC does with it

Most modern DAC chips are not one-bit devices. They convert everything, PCM and DSD alike, to their own internal format. Sending them DSD natively means the DAC does that conversion instead of the player. Whether that sounds different depends on the DAC’s filters, not on magic in the format.

Native DSD and DoP

To get DSD to a DAC untouched, a player sends it natively (a DSD format the USB driver supports) or as DoP, DSD packed inside PCM frames that a DoP-aware DAC unpacks. Both need specific DAC and driver support.

What MP95 does

MP95 converts DSD to PCM: up to 352.8 kHz on iPhone, iPad and Mac, 88.2 kHz on Android. It does not send native DSD or DoP. The upside is that DSF and DFF files play on any output, the phone’s own included, in one library with your FLAC, with their tags and artwork, and on Android without waiting for a conversion to finish.

Why DSD recordings often sound good

Many DSD releases come from small audiophile labels that record carefully and master gently. That care is audible in any format. A good DSD recording converted to good PCM sounds like a good recording.