[linux-audio-dev] Sidechains, was Re: [linux-audio-announce] [ANN] swh-plugins 0.3.4

Hi, Yes, I was wondering how the 3<-->2 port sidechain compressor plugin would be handled in hosts... Sidechains are a very powerful feature however and I'd want one for sure. I've been giving this some thinking, don't know if this has been discussed before... Theoretically speaking, the compressor sidechain is more or less just a special case for the more generic need: Audio-data used as control-data. What if the sidechain was a separate ladspa plugin that in turn uses some ipc mechanism to communicate to the plugin being controlled? I have no idea what kind of ipc is best for this, named pipes seem easy but they are probably slow, yes? By using one of the controls of the ladspa plugin to select which sidechain "channel" (e.g. 1-10) they should send and receive on (much like a comm-radio) you could have several different sidechains up and running simultaneously. This construction has a number of interesting side effects (pun not intended): * 1-n setups can be produced, one sidechain can control several effects. * Atleast with named pipes the control would be application agnostic. The sidechain would not need to be used in the same host as the effect plugin. * I don't know if other types of plugins are applicable to this, but since the sidechain is a separate plugin you could make _any_ plugin sidechain aware. mmmm audio controlled room-size for reverbs...mmmm :-D. * Very interesting things can be done if other values than boolean are possible, ramps and what not. Any thoughts? mmmm... what about a sidechain that sends on several channels, but with some kind of arpeggio algorithm??? :-D ...I should shut up... --- Moreover, I have only recently taking up recording......... again, after about two years of void (since I last used Windows for recording music), Ardour and MusE are getting quite usable! (now if I only could get rid of all those xruns :-/) Since starting to record again I've noticed there are some specific plugins I'm missing that I'd like to have if anyone has got the time to implement them. Top priority is a LADSPA stereo delay, I couldn't find one in Steves collection. But it would also be nice with: - stereo autopanner - auto sweeping filters. Apologies if these infact are available and it's just my poor eyesight. Regards, Robert