[LAU] Help with jack-volume please

Fons Adriaensen fons at linuxaudio.org
Wed Feb 17 10:12:09 CET 2021

On Tue, Feb 16, 2021 at 02:48:00PM -0500, drew Roberts wrote:
> I need to be able to use jack-volume:

As an alternative you could look at zita-jacktools:

class JackGainctl(JackClient):

    Multichannel dezippered audio gain control.

    The 'gain' and 'mute' settings are independent. A gain
    less than -120 dB is equivalent to 'off' (-inf dB).
    The initial gain is 'off', not muted.

    Gain changes are dezippered as follows:
    'off' -> 'on'  : 10 ms fade in.
    'on'  -> 'off' : 10 ms fade out.
    otherwise      : gain changes by max 6 dB for each 10 ms.


class JackMatrix(JackClient):

    Audio matrix with gain and delay controls for each input,
    output, and input-output pair.

    Gains are linear and can be negative to invert a signal.
    Use db2lin() to set gains in dB. Delays are in seconds.
    Absolute gain values lower than 1e-15 are set to zero. 
    Gain and delay changes are crossfaded over one Jack period.

With a few lines of Python you interface these to whatever 
you need.



More information about the Linux-audio-user mailing list