I have three DI tracks for bass, which I want to replay through Amplitube (only one track feeding per time).
 
If there was a channel insert function, I could send to the VST and have it return back to the track either pre or post FX, but the best I have been able to come up with is send the tracks to an aux bus that contains Amplitube, and mute the DI tracks.  The problem here is that I dont have individual fader control of each track when I do it this way.
 
Is there another way to have multiple tracks feed a single VST, with fader (output) control of each track? 
 
 

If I am understanding this and I'm really not sure I am try out putting the tracks to a buss that has the fader pulled down.  You can then have the send post fader on the tracks and control the send output with them. 

John
If I am understanding this and I'm really not sure I am try out putting the tracks to a buss that has the fader pulled down.  You can then have the send post fader on the tracks and control the send output with them. 

The problem with this (I think) is that the level sent to the VST amp will have less gain and will change the tonality.
 
Do you know what an insert is?  Imagine the external insert plug in, but one that works with a VST.  That is what I want!

The FX bin is a place for VST inserts! I guess what you're asking for is the ability for that to come back post FX, but even the inserts on my mixing desk don't offer that.

The FX bin is the equivalent of an insert point.  if you want amplitube to be post fx, and you want to use other FX, put them all in the FX bin and put Amplitube last in the bin.  You can change the order of VSTs in the FX bin just by dragging them up/down the list.
 
If you want the same amplitube for all the DI channels, set up one first the way you want it, then ctrl drag to the other two FX bins to copy it.

Maybe I'm misunderstanding the question - couldn't you control the output control of the tracks with their individual faders?

Assuming I interpret the following correctly: "Is there another way to have multiple tracks feed a single VST, with fader (output) control of each track?"...I believe the short answer is no IF what you want to do is mix three tracks into a single VST, then split the output of a single VST three ways so that these outputs join the three tracks that were mixed together, with the output inserting after the FX bin but before the channel fader.
 
Once the signals are mixed together to go into a single VST, there is no way to "unmix" them after the VST.
 
Karyn's solution is the simplest one: Three DI tracks, three inserts of AmpliTube with identical settings, three output controls.

The problem with putting Amplitube in each track FX bin is that I have three instances of the plugin running, and I need to keep the project light for the lowest latency.  If I use that strategy everywhere, then I will have a ton of instances running.
 
Perhaps another strategy would be to use/learn the comping feature as it seems to be able to have multiple virtual tracks per channel, but then I need to mess with automation for level variations instead of having separate tracks.
 
New to Sonar.. still figuring it out.

Anderton
Assuming I interpret the following correctly: "Is there another way to have multiple tracks feed a single VST, with fader (output) control of each track?"...I believe the short answer is no IF what you want to do is mix three tracks into a single VST, then split the output of a single VST three ways so that these outputs join the three tracks that were mixed together, with the output inserting after the FX bin but before the channel fader.
 
Once the signals are mixed together to go into a single VST, there is no way to "unmix" them after the VST.
 
Karyn's solution is the simplest one: Three DI tracks, three inserts of AmpliTube with identical settings, three output controls.

Yes, thats what I want.
 
Maybe I should buy an i7 and rebuild my daw.

200bpm
The problem with putting Amplitube in each track FX bin is that I have three instances of the plugin running, and I need to keep the project light for the lowest latency.  If I use that strategy everywhere, then I will have a ton of instances running.

Once you've got the sound you want you can freeze the track. This converts everything in the track to audio and turns off all the VSTs in it, so you get your latency back.  You can still mix as normal.  If you need to edit the track, un-freeze, make your edits, freeze again.