Test tones
Eight FLAC files at known sample-rate / bit-depth combinations. Each is a 5-second 1 kHz sine wave at -6 dBFS, stereo. Use them to verify what your audio chain is actually delivering at each tier.
| Rate | Bit depth | Use | File |
|---|---|---|---|
| 44.1 kHz | 16-bit | CD quality | 44100-16bit.flac |
| 44.1 kHz | 24-bit | CD rate, extended depth | 44100-24bit.flac |
| 48 kHz | 16-bit | Video / DAW project | 48000-16bit.flac |
| 48 kHz | 24-bit | DVD quality | 48000-24bit.flac |
| 88.2 kHz | 24-bit | 2× CD HiRes | 88200-24bit.flac |
| 96 kHz | 24-bit | HiRes 96/24 | 96000-24bit.flac |
| 176.4 kHz | 24-bit | 4× CD HiRes | 176400-24bit.flac |
| 192 kHz | 24-bit | Maximum HiRes | 192000-24bit.flac |
How to use
- Open Audio MIDI Setup (Spotlight → "Audio MIDI Setup"). Select your output device on the left. Note the current Format setting (e.g., 44100 Hz, 24-bit Integer).
- Download a test tone above. Open it with Music.app or VLC — both respect the source rate and pass it to CoreAudio.
- While the tone is playing, click the Bit Pedant menubar icon. Read the HAL physical and HAL virtual rows. They should match the device's Format setting in Audio MIDI Setup.
- Now flip the device's Format in Audio MIDI Setup to a different rate (e.g., from 44100 to 96000). Bit Pedant should reflect the new rate within ~1 second.
What to expect
For most apps (Music.app, VLC, browsers, Spotify, default Tidal), macOS's system mixer transparently resamples source audio to the device's nominal rate before it reaches the HAL. So the HAL virtual and physical rates will both equal whatever you set in Audio MIDI Setup, regardless of source file rate.
The real question is: does your device's nominal rate match the source you're playing? If you're streaming HiRes 24/96 and your device is locked at 44.1, the system mixer is silently downsampling — and you're not actually getting HiRes regardless of what your source app claims. Bit Pedant flags this in the Findings section when the source app's introspector can read its quality preference (Tidal, Apple Music).
To see HAL-level resampling, you need an exclusive-mode app (Audirvana, Roon, or Tidal with "Exclusive Mode" enabled in Settings). Those bypass the system mixer and push their source rate directly. If you set the device rate to a non-matching value, Bit Pedant's verdict flips to resampling.