[LAD] Routing signals in mixer (Ardour, Qtractor)

Jeremy Jongepier jeremy at autostatic.com
Wed Jul 7 09:32:34 UTC 2010


On 07/07/2010 09:49 AM, Louigi Verona wrote:
> Hello!
> 
> Both Ardour and Qtractor are capable sequencers. Ardour is getting midi
> soon, Qtractor is getting automation. All of this is good news.
> 
> I was wondering if the devs are interested in implementing routing
> signals in a mixer as the next important priority. This would allow not
> only effects chains which is usually very useful, but also usage of
> vocoders.
> At the moment it is impossible to use a vocoder plugin inside Ardour or
> Qtractor.
> 
> The beauty of vocoders is that they can be used not only on voice, but
> as electronic instruments as well. I am often using them to create
> beautiful textures, but in order for the result to be good,
> I need to automate parameters of the vocoder. LADSPA Vocoder, for
> instance, is capable of generating very beautiful sounds, but only if
> you can change the bands in real time, fade the in and out.
> Of course, sometimes it can be recorded live, but in many cases it needs
> to be automated and stored in a project.
> 
> Tell me what you think.
>

Hello Louigi,

I think it can already be done:
- In Qtractor create four tracks with corresponding buses: synth
(stereo), carrier (mono), vocoder (3 channels) and vocoder-mix (stereo)
- The vocoder track needs a corresponding bus with three channels, one
for the carrier and one for the incoming signal
- Have all tracks output their signal to their corresponding buses,
except for vocoder-mix of course, have it output to the Master output bus
- Load the vocoder LADSPA plugin into the vocoder track. I don't know
which input is the carrier and which one the stereo input but I think
you'll figure that out yourself
- Make the connections in QjackCtl's or Qtractor's Connections window:
connect the synth output bus ports to the vocoder input bus ports and
connect the carrier output bus port to the third vocoder input bus port.
Then connect two of the vocoder output bus ports (the ones that output a
signal, one of the outputs will be silent I guess) to the vocoder-mix
input bus ports.

Not sure if it works, but I managed to set up a similar effect chain
when it comes to using sidechain compression in Qtractor with the SC3
LADSPA compressor
(http://linux.autostatic.com/images/2010-07/sidechain.ogg). Works like a
charm so it should work with a vocoder plugin too.

Best,

Jeremy



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