I have q question about the behavior of TTS-1 synth compared to Dimension Pro.
 
I recently discovered the technique of "opening" a MIDI file in Sonar, inserting the TTS-1, assign the outputs of the MIDI tracks to the TTS-1 and, VIOLA!, all the tracks play back.
 
I tried the same technique using the Dimension Pro and it didn't work.
 
Are there default settings I need to set up on the Dimension to get it to behave the same way as the TTS-1 in this process.
 
As always, thanks for your support.

Currently there is no way to change the synth used by the automatic MIDI mapping process.

More importantly, Dim Pro is not a muilt-timbral synth like TTS-1; each intance of Dim Pro can normally play only one instrument/sound unless you specially create a patch that uses each of the four 'Elements' as a separate sound and set each Element to respond to a different channel.

As said, TTS-1 is Sonars only GM playback synth. 
It should load automatically when you open a midi file. 
If it doesn't then make sure your midi output ports are assigned to "none" in preferences. 
( thanks scook for pointing this out to me the other day) 
 
The TTS-1 will play songs the way the author intended them to sound.
From there you can insert better synths and improve things track by track. 
Example the SI Bass and Addictive drums will always make a huge difference. 

Thanks, folks.  Still trying to get my arms around this beast called Sonar.

We've all been there Tim, any questions, you know where we are