TTS-1 Drum Edit

Changing the pan setting in the TTS-1 window is a temporary setting, as you have discovered.

If you want to change the pan setting of an individual percussion sound you have to send a MIDI message to the synth.

See "PAN (GM2) [NRPN 1CH rrH]" in the "Using the Rhythm Edit Window" section of the TTS-1 help.
 
Cheers
Eddie

Just a thought,, do you have Session drummer with X3? I know you won't have Addictive drums, but session drummer has a GUI mixer that actually works. Changing much in TTS-1 take knowledge of System Exclusive messages and deeper midi editing. Not for the faint of heart. We used to have to know this stuff but now our drum software is very user friendly.
 And once you move on to Session Drummer and now even better we have Addictive drums, TTS_1 drums sound low quality by comparison. If I fire up my old project that used TTS-1 I immediately change over to AD.
I still like TTS-1 Kick. It works for me for a lot of songs, don't know why.
Addictive drums was the main reason I upgraded.
But even if all you have is Session Drummer your much better off if you want to fine tune the drum sound and placement.
Session drummer will paly any drum sounds, I even recorded my real drum kit and was using that. So You could actually take any sound from TTS-1 , sample it and have SD play it back.

Thanks, I do have SD3, I don't know if that's x3, I went with TTS-1 because I was looking for a brush kit and I liked the brush hits in TTS-1 better, just didn't know how difficult the kit was to edit. I'll have to look into sampling the brush hits and adding them to SD3 kit, but I've not gotten into that. I'm not a software-o-phile, so I'd usually rather be creating music than fiddling with the massive options of the software, and I'm usually willing to settle for something lesser as long as I get something that sounds good. But I'll look into that because I do SD3's layout of individual instruments. I do have AD2 solo in my Command Center, it says it's installed but I don't know where or how to engage it, I don't see it in my Programs list, or as an option to create an instrument in Sonar... but I'll look into that.

Yes and I'll agree the brushes in TTS-1 for certain songs are good. So what I do is use both. 
Example: 
Kick -TTS-1
Snare- TTS-1 
All the other drums Session Drummer or ? 
Simple matter of having your drum parts in there own tracks. 
 
The trick of transferring TTS_1 sounds into a sample to be used by other drum synths is not that hard once you know where the files are stored for the samples. 
 
Make a midi track, point at TTS-1  set to recording  
Slowly play each note on your Keyboard that has a drum sound. 
Now freeze the track to create an audio track. 
I open this in a wave editor but you can do it in Sonar too. 
Now just cut and paste each sound to it's own wave file, cut to the very start of each note and leave the decay as short as possible. Save each part and name. 
Now drop these into the Session drummer folder where the sounds are stored. 
 
This brings up a question --- Can you play your own samples with Addictive Drums? 

In lieu of using the brush samples in SD3 or some other sampler, I'd recommend you just bounce the brush part to an audio track, and use audio panning. Or use a second instance of TTS-1 just for that part.
 
I have one old hardware synth that allows independent panning of each instrument in the drum kit using SysX messages, but I'm pretty sure TTS-1 does not support this, and I would be surprised if there's a soft synth in existence that does. As mentioned, dedicated drum synths handle this need by providing a built-in mixer with each kit piece on its own channel and separate outputs for each channel if you want to mix in SONAR.