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Rainer Thelonius Balthasar Straschill wrote: > I'm currently reflecting the possibility of doing looping-related > performance in a speaker configuration with more than two channels. > ... > iv. Laptop: Apart from the fact that I didn't yet find a looper plugin I've been investigating a laptop-based system for surround looping. I don't have all the pieces put together yet, but I can relay what I've found out so far. First, understand the difference between 5.1 surround sound encoding, and just having more than 2 output channels. If the goal is to create a 5.1 surround mix to publish on a DVD, then you will need a 5.1 surround encoder. If you just want to route audio signals to 4 or more speakers during live performance, then you don't need any special "surround" support in software or hardware. You just need a computer audio interface that has at least four mono analog output channels, and software that can route signals to each of those channels. You would probably want to feed the audio interface channels into a mixer with a 4 channel output bus, then into a pair of stereo power amps. There are lots of mixer/amp possibilities, the important thing is the 4 output audio interface. If there will only be one performer, then the audio interface only needs to have one input channel, though it might be more convenient to have more depending on the choice of software. Next you need a VST host that supports multi-channel audio interfaces and multi-port plugins. Plogue Bidule, Audio Mulch, and EnergyXT are all very good. Audio Mulch is free, the others are under $100US. I'm not very familiar with Live!, but you should be able to route audio to all of the output channels provided by the interface. If you don't want to use the static loop triggering features of Live, it will be simpler to use a general VST host like Bidule. Now you need a looper plugin and a mixer plugin that can balance the looper output among the 4 audio output channels. The best mixer plugs for this purpose were designed for surround mixing, you pan the input signal in space by moving a puck around a 2 dimensional grid. A surround panner isn't required but it makes the job easier, and some support automated movement which is fun. There were some great ones here, but they seem to have been temporarily removed: http://acousmodules.free.fr/index_en.htm Most looping plugins are single channel, meaning they take a stereo input and produce a stereo output. If you just want a single looper positioned in surround, then run one instance of the looper patched into a surround panner. Boring. What is more interesting is running several instances of the looper and several instances of the panner. This gives you the ability to have several loops going, each at a different location in space. The problem with running multiple looping plugins is that they are difficult to synchronize. Since the plugins aren't aware of each other, they need to support some form of synchronization with the VST host, usually this means quantizing record start/end on a "beat" or "bar" boundary. Not all plugins support this. This also requires the use of a timer or sequencer plugin that can generate clocks to be sent to each looper plugin. A timer is integrated with Audio Mulch, I think Bidule has a timer plugin, I'm not sure about EnergyXT. What would be nice is if there were a looper plugin that supported more than one concurrent loop internally, maintained it's own synchronization, and could route each loop to four or more output ports. Wait! What about Mobius? (Oh, come on, you knew I'd be bringing that up eventually :-) With Mobius, you would run a single instance of the plugin, then route each of the 8 tracks to a different output port. Patch the Mobius output ports to 4 or more surround panners, then patch the surround panners to the 4 channels of the audio interface. A Mobius track is essentially an autonomous looper with features similar to that of the EDP. But the tracks are also aware of each other so you can initialize them to have exactly the same cycle length as another, resulting in multiple loops that are always in perfect sync. You can control each loop track from the same MIDI controller and feed them from the same audio input. If Mobius is on the list of looping plugins you don't like, I'd be happy to hear what you don't like about it. Maybe it can be fixed. Jeff