Optimizing latency via JACK

Hi there,

I’ve got some problems adjusting the latency compensation for JACK+Ardour.

I’m using Ardour 3, Ubuntu Studio and an Edirol UA-25 soundcard. JACK settings: Frames/Period 1024; Periods/Puffer 2.

I’ve measured the latency via jack_delay;

3251.767 frames 73.736 ms

There are contrasting opinions on what jack_delay already calculates and on what I have to subtract.

I already thought about doing the following:
3252-(2*1024) = 1204
-> input latency 602
-> output latency 602

Is this correct?


If you let Ardour 3.5 start JACK it can do the calibration for you automatically.

If you run jack_iodelay (which is part of JACK) rather than jack_delay (its ancestor) it will do the math for you automatically.

If you do neither of those, then you need to do the math you did above, which is correct.

Thanks Paul!

If I use the jack_delay calculation (602/602) and if I don’t explicitly prompt Ardour 3.5 to do the calibration, it won’t compensate it twice, will it?