# Reverb

> An eight-line modulated feedback-delay network with room, hall and plate-like tunings.

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

Reverb adds the sense of a space around a sound by blending in a dense, fading tail.

## What it does

The input is delayed by Pre-delay and fed into an eight-line feedback-delay network. A mixing matrix at Diffusion spreads energy between the lines, Damping darkens the tail as it decays, and a small Modulation avoids a metallic sound. Space selects Room, Hall or Plate-like tunings, and Size scales the whole network. Mix blends the tail with the dry signal. Each channel keeps its own history. Freeze removes new input and holds the energy of the network so the tail does not decay; a frozen network reports an infinite tail.

## When to use it

Use it to place a sound in a room, to smooth a mix or to make pads and drones. Use [Delay](https://docs.tune.toys/nodes/std.delay/) when you want distinct repeats.

## Ports

<!-- ports:start -->

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

<!-- ports:end -->

## Parameters

<!-- parameters:start -->

| Parameter    | Label      | Range        | Default | Unit | Scale  | Notes                                                                                                                   |
| ------------ | ---------- | ------------ | ------- | ---- | ------ | ----------------------------------------------------------------------------------------------------------------------- |
| `decay`      | Decay      | 0.1 to 12    | 1.8     | s    | log    | Nominal RT60 at the reference damping setting; Freeze suspends decay.                                                   |
| `damping`    | Damping    | 200 to 20000 | 6500    | Hz   | log    | Low-pass damping within the feedback network.                                                                           |
| `predelay`   | Pre-delay  | 0 to 100     | 10      | ms   | linear | Delay before the diffuse wet field.                                                                                     |
| `mix`        | Mix        | 0 to 1       | 0.3     |      | linear | Dry/wet blend. Processing latency is aligned before blending.                                                           |
| `type`       | Space      | 0 to 2       | 0       |      | linear | Selects the implemented algorithm. Choices are discrete and are not LFO targets. Choices: 0 Room, 1 Hall, 2 Plate-like. |
| `size`       | Size       | 0.5 to 2     | 1       |      | linear | Scales the prepared feedback-delay network.                                                                             |
| `diffusion`  | Diffusion  | 0 to 1       | 0.85    |      | linear | Mixing depth of the contractive Householder feedback matrix.                                                            |
| `modulation` | Modulation | 0 to 2       | 0.4     | ms   | linear | Small slow delay modulation for a less metallic tail.                                                                   |
| `freeze`     | Freeze     | 0 to 1       | 0       |      | linear | Removes excitation and holds network energy. A frozen network reports an infinite tail. Choices: 0 Off, 1 On.           |

<!-- parameters:end -->

### Decay (`decay`)

The nominal time, 0.1 to 12 s, for the tail to fade (RT60) at the reference damping. Freeze suspends it.

### Damping (`damping`)

A low-pass in the feedback network, 200 to 20000 Hz. Lower values give a darker, warmer tail.

### Pre-delay (`predelay`)

The delay before the wet field, 0 to 100 ms.

### Mix (`mix`)

Dry and wet blend. Processing latency is aligned before blending.

### Space (`type`)

Room, Hall or Plate-like. A discrete choice.

### Size (`size`)

Scales the prepared network from 0.5 to 2.

### Diffusion (`diffusion`)

The mixing depth of the feedback matrix, from 0 to 1. Higher values sound smoother and denser.

### Modulation (`modulation`)

A small, slow delay modulation from 0 to 2 ms that makes the tail less metallic.

### Freeze (`freeze`)

Off or On. When on, new input stops entering the network and the tail holds.

## Tips

- A little Pre-delay keeps the start of a sound clear of its own tail.
- Lower Damping for dark, warm spaces.
- Freeze with a long Decay makes an instant drone from a short sound.

## See also

[Delay](https://docs.tune.toys/nodes/std.delay/), [Chorus](https://docs.tune.toys/nodes/std.chorus/), [Noise](https://docs.tune.toys/nodes/std.noise/).