What is bit-perfect on a Mac and how to get it
“Bit-perfect” means the data reaching your DAC is exactly the data in the file: no resampling, no mixing with other sounds and no digital volume changes. It is the foundation of audiophile playback, and on a Mac you can get it, but it is not on by default.
Why macOS can alter the signal
Apps normally don’t talk to the DAC directly: they go through the Core Audio mixer. In that shared mode, the system:
- Mixes the audio of every app (alerts, video, browser) into a single stream.
- Converts the sample rate to the one set on the device (for example, a 96 kHz file played out at 48 kHz).
- Applies the system volume in software, which changes the samples.
How to get bit-perfect playback
- Use a clean digital output: a DAC or speakers over USB or Thunderbolt. The Mac’s own output also works.
- Turn on exclusive mode (the player takes control of the device) and automatic sample-rate switching, so each song plays at its original rate.
- Keep volume on the DAC itself or fixed at 100 %, with no digital volume.
- Turn off DSP, ReplayGain and crossfade.
What breaks it
- Bluetooth: the signal is compressed by a codec, so it is never bit-perfect.
- AirPlay: it goes up to CD quality, so higher-resolution files are reduced.
- Equalizer, convolution or digital volume: they change the samples on purpose.
- Shared mode without automatic sample rate: the system resamples.
How to check it in Sonora
Sonora always shows the signal path: from the file to the DAC, with the sample rate at each step. If nothing alters it, you’ll see bit-perfect; if you turn on the Hi-Fi Tower equalizer, convolution or digital volume, it marks it as “Processing”. You don’t have to take it on trust: you can see it.
Can you hear the difference? It depends on your gear, your ears and the material. A well-done sample-rate conversion is often hard to tell apart. What bit-perfect gives you is control and certainty: you know nothing touches the signal between the file and the DAC, and you decide when to process it.
Try it with your library
Sonora is a native macOS player (Apple silicon, macOS 14 or later). Try it free for 14 days with every feature, no card and no sign-up.