> ## Documentation Index
> Fetch the complete documentation index at: https://comfytv.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Audio Mix

> Layer up to four audio tracks into one, each with its own volume and stereo position — a mini mixing desk.

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## What this node does

**Audio Mix** sums up to four `COMFYTV_AUDIO` sources (A, B, C, D) into a single stereo track. Each channel has independent **gain** and **pan**, so you can balance a voiceover against music and sound effects in one node. At least one source must be wired; empty inputs are skipped.

It outputs one `COMFYTV_AUDIO` snapshot and has a ▶ **Run** (FFmpeg does the mix).

To feed native ComfyUI `AUDIO` in or out, insert a **Bridge** — see [bridges.md](https://github.com/jtydhr88/ComfyTV/blob/main/docs/bridges.md).

## When to use it

* Combine narration, a music bed, and SFX into a finished mix.
* Set relative levels between tracks and spread them across the stereo field.
* Re-assemble stems (from **Audio Stem Split**) after processing them individually.

## Parameters

### pan\_law

How panning affects loudness across the stereo field: `audacity` (default) or `constant_power`. `constant_power` keeps perceived loudness steadier as a source moves left/right; `audacity` matches Audacity's convention.

### dither

Dithering applied when reducing bit depth: `none` (default), `tpdf`, or `shaped`. Add dither (`tpdf` is a safe general choice) when exporting to a lower bit depth to avoid quantization artifacts.

### gain\_a / gain\_b / gain\_c / gain\_d

Level for each source in decibels. Range **-60 to +12 dB**, default **0** (unchanged). Set unwired channels are ignored.

### pan\_a / pan\_b / pan\_c / pan\_d

Stereo position for each source. Range **-1 to +1**, default **0** (center). **-1** = hard left, **+1** = hard right.

## Outputs

| Output    | Type            | Meaning                                       |
| --------- | --------------- | --------------------------------------------- |
| **audio** | `COMFYTV_AUDIO` | The four sources summed into one stereo track |

## Tips

* Watch the summed level: several tracks at 0 dB can clip. Pull individual gains down a few dB if the mix distorts.
* Only wired inputs count — you can use just two or three sources without touching the others.

## Related nodes

* **Audio Duck** — automatically dip one track under another instead of setting fixed levels.
* **Audio Stem Split** — separates a mix into stems that you can reprocess and re-mix here.
* **Audio Crossfade** — join two clips in sequence rather than layering them.