# Combine channels

> Concatenate two audio buses, preserving every channel without mixing.

Source: https://docs.tune.toys/nodes/std.combine/

Combine channels joins two audio buses end to end into one wider bundle. Nothing is summed or changed.

## What it does

The output channels are those of input A followed by those of input B. Joining a mono signal with a mono signal gives a two-channel bundle, and a stereo bundle with a mono signal gives three channels. Every channel is preserved exactly. The node has no parameters.

## When to use it

Use it to build a multichannel bundle from separate sources, or to pair a stereo bed with extra lanes. Use [Select channels](https://docs.tune.toys/nodes/std.select/) to take bundles apart again, [Channel matrix](https://docs.tune.toys/nodes/std.matrix/) to reroute or mix lanes, and [Mixer](https://docs.tune.toys/nodes/std.mixer/) to add signals together.

## Ports

<!-- ports:start -->

| Port    | Direction | Signal | Lanes                   |
| ------- | --------- | ------ | ----------------------- |
| `a`     | Input     | Audio  | Inferred from the cable |
| `b`     | Input     | Audio  | Inferred from the cable |
| `audio` | Output    | Audio  | Inferred from the cable |

<!-- ports:end -->

## Parameters

<!-- parameters:start -->

This node has no numeric parameters.

<!-- parameters:end -->

This node has no parameters. Its behavior comes from the width of the signals you connect. The channel count of the combined result is the sum of the channels on A and B, up to the 32-channel limit.

## Tips

- Mono to two channels: combine two mono sources, then feed the result into a stereo output.
- The output width is a sum; if it does not match the next node's input, use a Channel matrix or Select channels.
- See [Multichannel audio](https://docs.tune.toys/concepts/multichannel/) for width rules.

## See also

[Select channels](https://docs.tune.toys/nodes/std.select/), [Channel matrix](https://docs.tune.toys/nodes/std.matrix/), [Mixer](https://docs.tune.toys/nodes/std.mixer/), [Cables](https://docs.tune.toys/concepts/cables/).