Can Sonar be used in live performance?

Yes, it can.
 
If you are going to play along with backing tracks, I would suggest:
 
1. Export each project's tracks (the ones that will be the backing tracks)
2. Do the above for each project.
3.  Now create a new project - this will be for the gig
4.  Populate the new project by importing the various song files made from the exported tracks from step 1.  Import can either be as one song after another on one track, or each imported song can be on its own track.
5.  Control playback as needed, with space bar and/or solo/mute
6.  Become uber famous
 
The above is one approach, of many.
 
Bob Bone
 

Yep - absolutely. I run a project called Kicksville that probably implements Sonar in our live show to an extent way beyond anything else I've seen. But, depending on what your needs are, programs like Abelton Live or a VST host like Forte might be better. We use Forte alongside Sonar, and it's a really nice combination.
 
We basically do what Bob suggested: the whole show is laid out in one giant project file. I press start at the beginning of the show, and barring some horrible screw-up, it runs straight through. We have a really complicated, 72-input show, with all sorts of multimedia stuff going on. The tech is actually part of the show, so everything is run from the stage. We feed a stereo mix to FOH, steal their house DMX control, and Sonar pretty much runs everything:
 
1. up to 8 tracks of playback
2. 40-ish MIDI tracks for automation

• all audio console automation: fader, mute, pan, effect changes, effect and monitor send automation, routing, etc.
• program change automation for the 4 remote computers running Forte (VST & VSTi host)
• all video switching automation: source, transitions, output, etc.
• all lighting automation: MIDI notes trigger the "go" cues in Light Factory (computer-based lighting console)

3. MTC source for video world, also sends MTC to an analog filter (Filter Factory) to be able to do sync-ed sequencing
4. records a 2-track feed from our onstage console
5. also used for all pre-production, including mixing playback stems and providing reference levels to calibrate external gear
6. main Sonar screen run through a VGA splitter to monitors all over the stage for cueing, plus one large screen on the stage edge so the audience can see what's going on.
 
Here's an example - the audio is actually the 2-track direct feed back into Sonar, with no editing in post: http://youtu.be/omElhthKQIQ
 
We've never had any kind of problem with Sonar in the 7 years of touring, but part of that is what we've found to be the key for any computer-based system: don't stress the machine's capabilities, and you will rarely have problems. Even though the Kicksville show is pretty ginormous, the machine running Sonar isn't even breaking a sweat. Running a couple of playback tracks and a pile of MIDI tracks is nothing. All the heavy lifting (like hosting VSTs and whatnot) is spread around on different computers, so no one single machine is getting beat up on.
 
So...yeah...sorry for the really long answer to a short question ;-) Hope this at least helps explain that you can do an awful lot with Sonar if you want!

I too have used Sonar and Forte side by side for a really powerful combination in live situations.
 
We were able to present incredibly complex music live, without issues, using that same approach of keeping the load on the computers low, while still exploiting the capabilities of both Sonar and Forte.
 
Bob Bone
 

fascinating, conrad. just curious - what were the 8 tracks you played to, seemed like most instruments were live...

David, it depends on the song - some have quite a bit of playback, some have none. The tracks are broken down into 5 stereo tracks: drums/perc, instrument, vocals, click, and a cue track (used for a couple of songs to give the singers their note, since their part starts before the rest of the band).
 
We also have our individual parts in the project file, but they're muted. If somebody's rig goes down during the show, I can un-mute the person's part, and the playback covers them until they can catch up.
 
The video I posted earlier, Once In A Lifetime, is mostly live, but there is a wee bit of keyboards and a drum loop in one section. Here's an example of something with a little more playback, again mostly some keyboard sounds and a drum loop: http://youtu.be/8KBzY_HNLCU
 
One of the goals with our sound design was to make it almost impossible to tell by listening what's live and what isn't. That's the reason we put a VGA monitor on the downstage edge duplicating the main Sonar window - most large-scale touring artists are using playback, but they're hiding it offstage somewhere. We want the audience to know exactly what's going on, and to show 'em how it's done. ;-)

Interesting work kicksville. Subscribed to your YouTube channel.

Love your monitor idea!:-)

I too use it for live performances. Live Theater to be exact. In my use Sonar sends MTC to the lighting board and midi program changes to the mixing console, as well as music and SFX to 8 different sends throughout the theater. I'm also sending VST effects into the live mics and instruments. The Playlist feature is essential to me in all of this. And it finally works again in sonar X3e!

Thanks so much for the detailed responses.  I am totally impressed both with the responses and with the facts. I am just planning to offer up my set up as part of a variety show that individuals in our Chorus are performing  in June.  If someday I (we) become uber famous I will have ya'll to thank for it.   BTW  is "uber" short for "super"? 
 
As an aside "Kicksville"; my name is also "Conrad".  Back in the fifties when Joe McCarthy was running the House Unamerican Committee looking under every  rock for "Commies"  my unkind classmates would call me "Comrad".  It was quite hurtful ... hurtful, that is,  until I found that the Name "Conrad" means "wise and mighty counselor".  I proudly  made it known to my classmates that my name  was quite honorable.  Never again throughout my  many years did I feel badly about carrying it.