Definitely impressed with the plugin, tried it. Trying hard to work out how I would use it in my workflow it would probably confuse me to be honest, however I'm all for flexibility if people want it. Without trying to hijack here this is the other enhancement I would really like...

subtlearts
I'm not at my DAW just now to try it, but could this plugin not possibly be used to make that happen? Route the output of the synth or FX track to another track via the sidechain mixer, then record the track in real time? 

I tried it thinking it might, and all works great until you arm record on the track. There is a workaround (via use of a dummy MIDI clip) on the other thread. I think you can also get other plugins that will handle it. Still there are other uses for this particular plugin we are talking about here.
 
Cheers..

I just tried thie plugin and it works like a charm! This plugins is sooo awesome!!! Many thanks to whoever developed this one!!!

hanstheman
Im now experiencing problems using the plugin - it might be due to platinum and not the sidechain mixer in itself, just want to warn people.
Now it forces mono on its inputs, and suddenly this instance has disappeared(I cannot route to it anymore). Then I created a new instances that worked well, deleted the old instances with the strange mono behaoviour, and suddenly the new instance become mono and I cant route new tracks to it(it has disappeared on the list just the same)!!!
So just a general warning on platinum - do check that your sidechain mixer doesnt force mono.  
In any case, Im experiencing ton of weird behaovour in platinum - x3 works much better with vsts. 
Also the mix recall feature resets gain staging for my vst3 plugins, but thats a different story entirely... 
And kontakt player doesnt work... And plugins that turn up as vst3 in x3 turns up vst2 in platinum etc.... 

The mono behavior is a known issue. See Noel's reply to this issue here. It is due to the way Sonar treats sidechain inputs to a plugin. The bottom line is that if the very 1st input to a plugin is from a mono source, then Sonar will force all subsequent inputs to mono as well. The way to work around it is to ensure you don't feed mono inputs to the plugin, or if that is not possible, ensure the 1st input is stereo. However I'm not sure what qualifies as the "1st" input... How the tracks are sorted in the track list, or in the order they were added to the plugin.
 
I think this can really be seen as a bug in Sonar, since the plugin presents the sidechain input as stereo, yet Sonar forces it to mono based on the 1st input's interleave. It should only treat it as mono if all inputs are mono, not just the 1st one.
 
EDIT: An alternative way to work around this issue is to insert 2 sidechain mixer plugins into the FX bin. Feed all mono inputs to one of them, and all stereo inputs to the other one. Since the plugin mixes the sidechain input with the signal passing through it, you will get the correct behavior.
 
EDIT EDIT: BTW this thread has more details, and mentions the mono issue as well. I have not seen the issue with disappearing inputs. There seems to be some weird things in general going on in Sonar for you. If you know of a way to repro the issue with the sidechain inputs disappearing, let me know and I'll try it. The sidechain mixer plugin is really very simple - it just tells Sonar it has 2 stereo inputs and one stereo output. It doesn't have much control as to what Sonar does with that info.

Yes Sonar will not list an input to sidechain mixer if it will result in a loop. This is a good thing because you don't want to accidentally create such a loop and blow your ears or speakers! So it is possible that the routing you were trying to make would have resulted in such a loop.
 
In general I'm not hearing a lot of bad things about Sonar Platinum compared to previous releases (other than C3), so your bad experience is surprising. I wonder if installing on top of X3 might cause issues. Maybe Sonar is picking up an older X3 DLL or something, who knows. If you continue to see these problems, it might be worth uninstalling Sonar, wiping the folder, and then do a clean install.
 
But if you installed via C3 I believe Platinum would install in a different location than C3. So in theory they should not interfere with each other, and you should be able to run either C3 or Platinum.

I just installed sonar from the command center, without any errors. 
My sonar platinum is installed in the same folder as x3, they share vst plugins. 
In general Ive experienced some problems with vsts, sometimes sonar picks the 32 bit versions instead of 64 bit, one vst had delay compensation turned off etc.. but vst is a problem in general since they tend to install themselves in 5 different places on the drive, sometimes I have to manually move the correct ones to sonars vst folder. 
Ok, if my problems are not normal my guess would be to reinstall everything.