Since I'm using an older version of sonar that doesn't have matrix view this is kind of a guess, but I think you should be able to record a matrix performance using the mouse and clicking the cell headers. Also, I don't think you connect a soft synth instrument to the matrix but the other way around meaning the matrix can trigger a soft synth. But since your using audio clips in the matrix you shouldn't even need any soft synth connected to the matrix. 

I'm not sure if this practical, but, I wonder if you could use each clip as a sample in something like Dropzone or Session Drummer and then trigger via MIDI notes.  IOW, you would record each clip sequence you want by ""playing" the samples in the desired order.
 

Calkwalker

FastBikerBoy

If it's easy triggering then wr's suggestion may be the way to go. If you want more info on the matrix there's the SWA Complete Sonar X2 promo video on my youtube page which is the Matrix chapter, that might be useful.

Thanks for the Matrix video and suggestions.  Your video, the X1 Reference Guide, and other resources all suggest that only an external MIDI instrument/controller can be used to establish a MIDI trigger (which is why they call it "MIDI remote control" I suppose).  I tried creating a MIDI track and an associated instrument track, but when I turn on "MIDI Learn" in the Matrix View, it does not recognize an internally-generated MIDI note (output by the synth plugin to the Master Bus) as a triggering event.
 
My assumption at this point is that the triggering MIDI event must be present on SONAR's input bus in order to be recognized, which is disappointing, because I don't have an external controller.  I don't know if it's possible to route a MIDI instrument output to the input bus to make it look like an external device...

 

You're correct. Triggering using MIDI learn does require an external device as the trigger. Cells can be also triggered though by clicking on them with the mouse or pressing enter while it is the selected cell. That's the method I'm using in the videos.

SteveC's suggestion would work as well but even then it'll be easier with an external controller/keyboard. As far as I know there's no easy way of routing MIDI instrument output to an input although some synths can be set up to echo their MIDI output but that is unlikely to help triggering cells in the matrix.

Yes, I think SteveC's idea would work.  Cyclone is another choice for that approach.

Or, if you want to stick with Matrix, you could try using a software MIDI controller to trigger the cells, like the one talked about in this old thread.

http://forum.cakewalk.com/tm.aspx?m=1739973

wr
Or, if you want to stick with Matrix, you could try using a software MIDI controller to trigger the cells, like the one talked about in this old thread.

http://forum.cakewalk.com/tm.aspx?m=1739973

I've been looking into controlling stuff from my PC keyboard (with my left hand, while playing my 2 octave midi keyboard with my right) and had found just about nothing until this morning, when I came across chirp virtual midi keyboard controller.
 
Looks just like what I need though I haven't tried it yet.  Here's a short video.  Might be useful to Calkwalker as well.   It's 20$.