---
name: "alsa_delay"
section: "1"
platform: "linux"
package: "zita-alsa-pcmi-utils"
version: "0.6.1-1.1+b1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/alsa_delay"
---

# alsa\_delay(1)

measure round-trip latency of a soundcard

## NAME

alsa\_delay - measure round-trip latency of a soundcard

## SYNOPSIS

**alsa\_delay** playdev captdev fsamp frsize nfrags

## DESCRIPTION

This tool can be used to measure the round-trip latency of a soundcard. To do this, start the program and connect like this:

```
  alsa_delay -> playdev -> cable from soundcard output to input -> captdev -> alsa_delay
```

**alsa\_delay** should be able to measure the round-trip latency with an accuracy of around 1/1000 of a sample. The assumption is, that the latency is more or less independent of frequency, and that the cable between soundcard output and input has virtually zero latency.

## ARGUMENTS

- **playdev**

  ALSA playback device (e.g.: hw:0)

- **captdev**

  ALSA capture device (e.g.: hw:0)

- **fsamp**

  Sample rate (e.g.: 48000)

- **frsize**

  Period size (e.g.: 256)

- **nfrags**

  Number of fragments (e.g.: 2)

## EXAMPLES

This will measure and display the round-trip latency of soundcard **hw:0** using 48kHz samplerate, and 10 fragments each 2048 samples.

```
  alsa_delay hw:0 hw:0 48000 2048 10
```

## NOTES

**alsa\_delay** is a port of **jack\_delay** (by the same author) to ALSA.

## AUTHOR

zita-alsa-pcmi was written by Fons Adriaensen \<fons@linuxaudio.org\>.

This manual page was written by IOhannes m zmoelnig \<zmoelnig@iem.at\> for the Debian project (but may be used by others).