On Mon, Mar 04, 2013 at 10:53:30PM +0100, Chris Bungue wrote:
I work with KXstudio and Unbuntu 12.04. Normally I
think is on
KXstudio cadence the main tool for start and stop jack, but I like
qjackct. Most of the time I use both tools. Now I have seen that
cadence and qjackct shows different latency. Although both have the
same settings. Cadence always shows exactly the half of the value than
qjackct.
Which latency value of both is right?
Depending on how you define latency both could be right.
Qjackctl shows the sum of input and output latency - the time a
signal takes from an input of your soundcard to an output if
you connect the corrsponding Jack ports [1].
I don't know Cadence but apparently it shows just the input
and/or output latency separately, or it gets it wrong.
If you use -n 2 (2 periods) then input and output latency
are equal. If n > 2 then they are not, and Cadence *should*
show two different values, and the sum of those should be the
value shown by Qjackctl.
So try -n 3 and see what Cadence tells you...
[1] ignoring any additional HW delays that ALSA/Jack/Qjackctl
don't know about. You can measure the real delay using jack_delay.
Ciao,
--
FA
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It's also a pipe-dream, founded on self-delusion, nerd hubris
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