If you are asking what is dithering, here is the short answer: dithering is a tiny amount of carefully shaped noise added to audio when you reduce its bit depth (for example, from 24-bit down to 16-bit). It masks the harsh distortion that would otherwise appear in the quietest parts of the signal. Used at the right moment, it makes a lower-bit-depth file sound cleaner.
Quick answer
- Dither is low-level noise added when reducing bit depth.
- It hides quantisation distortion in quiet passages and fades.
- Apply it only at the final bit-depth reduction (e.g. exporting a 16-bit file).
- Apply it once, as the last step, never repeatedly.
Why dithering exists
When you lower bit depth, you reduce the number of values available to describe each sample. The audio has to be rounded to the nearest available value, a process called quantisation. In loud passages this rounding is harmless, but in very quiet passages and fade-outs it produces a correlated, granular distortion that the ear hears as harshness rather than gentle noise. Dithering replaces that ugly distortion with a smooth, far less objectionable noise floor. This sits alongside the concepts in our guide to sample rate and bit depth.
What is dithering doing?
By adding random noise just before the bit-depth reduction, dither decorrelates the quantisation error from the signal. Instead of distortion that tracks the music (which the ear notices), you get a constant, very low-level hiss that the ear largely ignores. Many dither algorithms also use noise shaping, which pushes that noise into frequency ranges where human hearing is less sensitive, making it even harder to notice.
When should you use dither?
The rule is simple: dither only when you reduce bit depth, and only once, as the very last step. Common cases:
- Exporting a 16-bit file (such as for CD) from a 24-bit project — dither.
- Bouncing a 24-bit master to 16-bit — dither on that export.
- Staying at 24-bit or 32-bit float — no dither needed.
If you are delivering 24-bit files (common for streaming and most mastering), you usually do not dither at all. Loudness and delivery formats are covered in how loud your master should be.
How to apply dither correctly
Place the dither as the final process in your master chain or in your DAW’s export dialog, after the limiter. Set the dither’s target bit depth to match your output (16-bit for CD-quality). Crucially, apply it only once — re-dithering an already-dithered file adds noise on noise. Most DAWs and mastering tools include a dither option in the export settings or as a dedicated plugin (for example, the dither modules found in mastering suites).
For the full mastering workflow this fits into, see what mastering is and the wider mixing and mastering hub.
Frequently asked questions
Do I always need to dither?
No. You only dither when reducing bit depth, such as bouncing a 24-bit project to a 16-bit file. If your output stays at 24-bit or 32-bit float, dithering is unnecessary.
Can I hear dither?
Rarely, and only if you turn it up very loud in a silent passage. Properly applied dither sits far below the music as a faint, smooth noise floor that is far less noticeable than the distortion it replaces.
Should I dither before or after the limiter?
After. Dither is the final step in the chain, applied at the point of bit-depth reduction, so it goes after the limiter and any other processing. Apply it only once.
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