Helllo Ico, > I have been messing with the ambisonic plugins provided in the CMT ladspa > collection. I am namely looking into a simple implementation of B-format > 1ch->4ch encoder. The problem is that I am failing to figure out how to use > this on a simple mono (non-encoded) sound input in order to control its > diffusion over 4 channels. I'm not sure what you mean by diffusion. For a mono source, you basically have two options: 1. Just send it to the B-format W channel, and not use X,Y,Z Thechnically that's not a 'legal' B format, but what you get is that the sound will come equally loud out of all speakers. 2. Use a B-format panner to put it into a particular direction. Remember that ambisonics encodes source direction, not position, i.e. it does not include any notion of distance. This is normally encoded by changing the direct / reflections / reverb ratios. Regarding the CMT set of ambisonics plugins, I remember having tested some of them at least a year ago and the conclusion was they have some problems. > When running it via Ardour and sending it to 4 > separate busses via this plugin, even though the x, y, and z coordinates do > affect the output of the 4 channels, they do not conform to the expected > 3,4,2,1 output (I presume these correspond to 4 speaker outputs, but I am > also having doubts about this as well, so your help in understanding this > better would be most appreciated). Seems like you need two things: 1. a B-format panner for ardour, so you can mix a number of mono inputs, giving each of them a 'direction' and maybe (via additional outputs) controlling their distance, and 2. a B-format to 4 speaker decoder following the master mixer strip. I have these things in house, and I'm using them all the time, but they are not in a state suitable for release. They will be released some time, and if you need them badly, I could change some priorities... OTOH, I remember you've been exploring SuperCollider recently, and that has everything you need on board. Have a look at the PanB2, PanB and DecodeB2 Ugens. -- FA
