[LAD] JACK on Gigaport HD+ at 4800kHz (reduced channel count)

Fons Adriaensen fons at linuxaudio.org
Tue Feb 25 14:56:32 UTC 2014

On Tue, Feb 25, 2014 at 02:25:25PM +0100, Jörn Nettingsmeier wrote:

> If the maximum channel count is always fixed by the hardware, what
> is the point of the corresponding jackd option? As I said, I don't
> remember if ever doing something other than throwing the "cannot set
> channel count" error...

The -i and -o options probably work on 'plug' devices (and on aloop),
but AFAIK they are useless for hw: devices.

While developing zita-alsa-pcmi I wanted to add parameters to select
channels - this just never worked, only one value (all channels) 
being accepted in all of the tests I did. So now it works the opposite
way: you open the device and then read the number of channels that are
available. When using the mmap access mode it's easy enough to read/write
only the channels you want and to ignore the rest without any overhead,
so in practice this not a problem.



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It's also a pipe-dream, founded on self-delusion, nerd hubris
and hysterically inflated market opportunities. (Cory Doctorow)

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