Thanks BAPU. I did change the interleave on a mono track to stereo but the plug did not work as described. There may be something wrong somewhere in Sonar then. I even created a new project and recorded a mono track and changed it to stereo interleave. I don't know what's going on. Apparently the plugin is not splitting the signal.

Sorry...my day got turned upside down...I'll try again tomorrow.

No problem yorolpal, I appreciate you checking.

OK, here's what I found out.  If you use the mono to stereo version on a mono vocal...it doesn't matter what you have the interleave set to...the source and adt pan knobs seem to function as simple "gain" or "amount" knobs and NOT pan knobs.  All the way counterclockwise is all signal and all the way clockwise is no signal at all.  Weird.  If, however you instantiate the stereo version on a mono vocal and change the track interleave to stereo...it operates as per expected as pan knobs.  If you use either the mono or mono to stereo versions you certainly get the effect but it's just a blend of the source and the adt with no seeming way to pan the two.  WAVES may have to step in and explain a little better about this.  And, as always, it's quite possible I was doing something wrong.  But I don't think so.  Hope this helps.
 
PS:  Just tried the same sort of thing with my brainworx stereomaker plug.  Unless I switch the track interleave to stereo it behaves exactly like the ADT...BUT...if I switch the track interleave to stereo the it behaves as the ADT is SUPPOSED to.  Must be something between X3(e) and the plug not communicating right.  Or, again, I'm doing something wrong.

any words on the cpu hit guyz ? 

#Zo:  The CPU is noticeable but not prohibitive.  I instantiated 8 stereo instances of ADT, checked the CPU hit, deleted them and then, one at a time, did the same to a range of other plugs.  ADT used more than most.

yorolpal
OK, here's what I found out.  If you use the mono to stereo version on a mono vocal...it doesn't matter what you have the interleave set to...the source and adt pan knobs seem to function as simple "gain" or "amount" knobs and NOT pan knobs.  All the way counterclockwise is all signal and all the way clockwise is no signal at all.  Weird.  If, however you instantiate the stereo version on a mono vocal and change the track interleave to stereo...it operates as per expected as pan knobs.  If you use either the mono or mono to stereo versions you certainly get the effect but it's just a blend of the source and the adt with no seeming way to pan the two.  WAVES may have to step in and explain a little better about this.  And, as always, it's quite possible I was doing something wrong.  But I don't think so.  Hope this helps.
 
PS:  Just tried the same sort of thing with my brainworx stereomaker plug.  Unless I switch the track interleave to stereo it behaves exactly like the ADT...BUT...if I switch the track interleave to stereo the it behaves as the ADT is SUPPOSED to.  Must be something between X3(e) and the plug not communicating right.  Or, again, I'm doing something wrong.

 
Thanks for confirming this yorolpal. I thought I was crazy for a minute there.

I just received another response from Waves. See below.
 
Because of the specific mixer architecture in Sonar, It appears there is actually no use for the Mono->Stereo component under Sonar.
If you need a Mono to Stereo effect under Sonar, load the Stereo component on a track with a Mono audio file playing.

I wonder if changing to a new pan law setting would do anything at all? Also wonder what the odd "mixer architecture" is in Sonar that precludes this from working. Suppose we'll have to ask upstairs...ugh.

I've been testing it and found that it has to be the first plug inserted on the track to work. If there is a mono plug on the track already it won't work. At least for me it won't. Also any other plug used has to be stereo but I'm sure you knew that. I'm real curious to as to the mixer architecture. How different could it be compared to other DAW's?