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).

                                                    July 2013                                  zita-alsa-pcmi(1)