Hi Colin,..
you have several options..
(I am ignoring your audiointerface as I am not familiar with it) I use i.e. the RME Fireface 800 with Ocatmic D - expansions..
I've done several recordings and used different setups each time..
Variant a.) I connect every instrument/mic to the inputs of my a/d-converters.. and directly route them to the individual outputs.(cue mix, "0" latency) Those outputs feed the inputs of a mixer..->amp->speakers
(my rack has ~24 physical inputs and 24 physical outputs)
The RMEs have a flash-bios which keep the settings even when your laptop crashes.. (I think they even pass the signal when they run out of power.. not too sure about it though)..
So this setup is very safe.. no latency... and if the pc/laptop fails you can still do your performance without even noticing that there's a fault.
You can use any audiointerface with multiple in- and outputs.. they only have to support "direct monitoring", which is probably supported by all of them..
Variant b.)
I am still experimenting a bit with it.. but so far so good..
You connect all your instruments/mics to your audiointerface (multipe inputs necessary)
You enable input-monitoring within Sonar.. you mix within Sonar (use eqs, compression, reverb,..) and send it to your stereo-outs!
the stereo outs feed your power amp and speakers..
Now you have more downsides due to latency and failures..
the lower you set your latency the more you push your cpu..
so it's very essential to have a quite powerfull system (notebook)
same applies to your plugins.. the more plugins.. the more power you need..
the round-trip-latency depends very much on the audiointerface you use ! So you need to do some tests to see if your round-trip-latency is low enough for you to play along.
next downside,.. when the system fails (i.e. laptop).. your performance is ruined.. I mean not only the recording.. but your live-performance !
Why am I suggesting this method anyway ? 'cause you can get a very "pro"-sound out of the box without any additional ext. gear(mixer/effects).
So variant "a" gets the job done.. no risks.. you can shape your sound later at home..
variant "b" shapes your sound already on stage,.. you can still do a post-production later with all the benefits of variant "a"
Re-reading your post, your needs are a bit smaller..
You can probably get away with a stereo-audio/midinterface.
Connect the vocal-mic to the left input of your audiointerface.. connect the guitar to the right input of your audiointerface.. connect the piano via midi to the midi-input of that audiointerface..
There are several options for the routing..
For live-performances I can only recommend to use a pair of mics(condenser) for the audience/ambience..
With these additional mics your audiointerface would already need at least 4 mic-inputs..
remember that you yet only record the midis of your piano.. if you want to record the audio as well you'll need at least 6 mic-inputs..
If the "Motu 8pre" had 8 outputs, then that would be something to consider..
The Edirol FA-101 could get the job done.. only 2 mic inputs though..
I am a bit clueless to find "moderate" gear for your situation..
post edited by Frank Haas - 2008/10/11 11:23:35