Creating and controlling feedback

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metalhead93
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Hi everyone, I'd like to know if there's some way to create and control an audio feedback via signal routing, because I looked for opensource plugin simulating feedback pedals or whatever, but didn't find any. I know it might be very dangerous to re-route a signal from an out to the in of the same channel/track, but I was wondering if there's a way to simulate some good larsen effect using a cabinet simulation (for example LAconvolver or LePou Lecab, or Ignite Amps NadIR).
Thanks!

paul
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It is certainly possible to create feedback in a digital system. But ... digital feedback sounds absolutely nothing like analog feedback, which is the effect you're looking for. You can only do this properly with an actual analog signal (i.e. signal to speakers to microphones) - that is, a signal that leaves your computer and then re-enters it after passing through signal transducers and signal dectors of some kind.

mike@overtonedsp
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@paul: you can create analogue style feedback using DSP - there are plug-ins (though probably not many for linux) and effects boxes which simulate things like guitar / amp feedback using algorithms to emulate the delays, resonant behaviour of strings etc and other components within such a feedback 'loop' e.g. Karplus-Strong string synthesis.

RattusB
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Joined: 2008-10-11
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Guitarix has a feedback plugin.

paul
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Right, I realized after I posted this that a plugin could simulate it. I should have mentioned that, but now you guys have done it for me, so thanks. My point was that digital signal feedback caused by connections has no relationship to analog feedback. @metalhead93: you need a plugin for this, not routing signals.

metalhead93
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Thank you all. I'm working on OS X, so I'll probably look for some DSp.

caryoscelus
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While plugins can certainly emulate feedback, they don't give full control over it. They can only do this:

input->effects->feedback->output
              ^-----/

Routing-based feedback is more powerful: it lets you insert other effects between feedback output & input, like this:

input->effects->feedback->output
     ^--------------/

I tried this setup in ardour 5.4 and it worked fine at first, but not after saving/loading. When i tried again (with a new session), i noticed that connections created after feedback was introduced do not work either. This is kinda sad (checking bugtracker..)