Hey, folks,
 
I'm need to know how to do something I haven't done so far with Sonar:  Set up playback for a complete MIDI song I purchased.
 
When I open the file, I get a number of MIDI tracks, each with their own performance and separate documentation that let's me know the intended instrument for each track.
 
A number of questions come to mind now:
 
1.  Do I need a separate soft synth track for each instrument? OR
2.  Can I load a single multitimbral soft synth and set set up different instruments on different MIDI channels?
 
If someone know of any Youtube video showing how to set up a multitrack MIDI file for playback, that would be peachy.
 
Thanks in advance for your help.

If no MIDI output device is defined in SONAR preferences, opening a MIDI file causes SONAR to automatically setup the file with TTS-1. From there, replace instruments as desired.

I haven't done this in a while, but I typically just drag+drop it in to sonar, it comes out on different tracks (its a midi 1 file) then add synths as needed
(pretty much what Steve said, minus the TTS 1)

Actually Chuck,, MIDI files should always be "OPENED". 
Importing (or drag and drop) will lose important information about tempo etc. 
MIDI files will adapt to the project you already have open and nothing will play correctly. 
 
TTS-1 should automatically be loaded when you OPEN the file
Butt that said, for some reason right now this is not working for me on my main DAW. Works fine on my laptop,, both are running the latest version of PLat. 
 
But if TTS-1 does not load. then insert it manually to listen to the file.
 
A trick that speeds things up is insert the TTS_1,, then
"SELECT ALL"        "Tracks" / Selected tracks output  /  midi output  - TTS_1
and now all tracks will be pointed at it. 
Most all pre made MIDI files will sound the way the author intended with the TTS_1. 
And then you insert better synths and start improving the sound. 
 
I've worked with more than 50+ downloaded files this way. I'm in the process of re doing all 150+ of my backing tracks and upgrading the instruments. AD2 and real bass mostly. 

Cactus Music
 for some reason right now this is not working for me on my main DAW. Works fine on my laptop,, both are running the latest version of PLat. 
 

Automatic TTS-1 mapping only happens when no MIDI output device is selected in SONAR Preferences. By default I believe SONAR enables the MS GS Wavetable synth which prevents automatic MIDI file to TTS-1 mapping. Double check your MIDI output device preference setting.

Thanks Steve ,, that was it, My main DAW is set to my Scarlett midi port. My laptops list is empty. 

Cactus Music
Actually Chuck,, MIDI files should always be "OPENED". 
Importing (or drag and drop) will lose important information about tempo etc. 
MIDI files will adapt to the project you already have open and nothing will play correctly. 

You sure about that ?
Tempo yes I agree it will be lost..but what else ?
I've opened many Midi 1 files by just dragging and dropping them in sonar.
if you drag a Midi 1 file to an empty track, Sonar will load the Midi 1 file on separate tracks.
All lined up and ready to go. all you have to do is add the synths and drag the separate tracks to their new synth tracks.
 
I don't do it often, but once in a blue moon when im bored, I will download a Midi 1 file (karaoke Midi file)
from Free midi com and zero in on a particular instrument, bass, flute, exc.
 

Yes there is stuff like all the system exclusive data which is not imported. That data can make a huge difference to the little details people add to the files. The song will play but it will not sound the way the author had made it. 
 
I just tried this: 
I dragged and dropped a midi file from the media browser into the 16 track midi template.  It is all wrong. It sounds terrible.
There is no TTS-1 so I had to add it, and there is no effects or panning on the tracks, it seems to play the correct  instruments but some are playing in the wrong octave. The tempo is wrong so now your guessing. was it a 3/4 song? ,, if so your measures are wrong. 
The tracks are only numbered 1 through 16 so you have to solo them and name them. on and on.. this is a lot of work! 
 
I then opened the same file and the tempo and everything is all there and the song sounds way better, exactly the way it was written.   
The tracks are all named correctly, the TTS_1 was automatically inserted and configured and all I do is open,, and hit play..  certainly the best and only way to fly. 
 
Importing or drag and dropping midi is for working with midi loops, not whole songs. 

Cactus Music
 
I then opened the same file and the tempo and everything is all there and the song sounds way better, exactly the way it was written.   
 

Well it looks like im learning something new :-)
How exactly did you open the midi 1 File ? (vs importing)

You open it the way all files can be opened in Windows. 
1- Use Sonars file menu.. preferred method -- "OPEN" - browse for the file.. 
2- Double click the midi file icon, you need to set Sonar as the default program for this to work. otherwise Media Player or iTunes is the default. 
3- Right click the icon and choose "open with"  hopefully Sonar is on the list.