# Echo

From Audacity Development Manual
This effect repeats the audio you have selected again and again, normally softer each time. The delay time between each repeat is fixed, with no pause in between each repeat.

| Note carefully that when you apply an effect to a time-stretched clip the changed speed of the clip will be automatically rendered. If you apply an effect to a selection within a time-stretched clip then Audacity will split the original clip so that the selection can be rendered as part of applying the effect.

  Accessed by: Effect > Delay and Reverb > Echo

Unless your requested echo length (delay time) is less than the length of the selection, no echoes will be created. Also Echo does not generate additional audio beyond that selected. So if necessary you must add sufficient silence to the end of your track(s) to accommodate your echo settings.

  To add silence:

1. Click in the selection and press End on your keyboard, or choose Transport > Cursor To > Track End
2. Choose Generate > Silence
3. Choose the duration of the silence you want to add to the selected audio, and click OK.

This leaves the generated silence selected. Before running the Echo effect itself, click in the Track Control Panel to select both the original audio and the inserted silence (or hold Shift and press Home).

## Delay time (seconds)

The amount of delay between the echoes, in other words the length of each echo.

## Decay factor

Usually a number between 0 and 1. A value of 0 means no echo, and a value of 1 means that each echo is exactly as loud as the original, so this merely extends the current selection unchanged. A value of 0.5 reduces the amplitude or loudness of each echo by half each time, so the audio dies out quite slowly. Smaller values make it die out more quickly. Values above 1 increase the amplitude of the echo each time, which you could use as a special effect.

| Because echoes are often added to the original audio, the processed audio will often have a higher peak level than the original. If clipping results, you can Edit > Undo the Echo effect, Effect > Amplify to a lower level, then apply Echo again.

Using Echo for loops: Echo can be used to create a simple loop with volume changes without any problem about gaps between each segment of the loop.

- If you want a loop with no volume changes, use Effect > Repeat instead.
- You can also create echoes with Effect > Delay which generates the additional audio needed for your chosen delay time and number of echoes.

## Links

|< Index of Effects, Generators and Analyzers

|< Effect Menu