Your issue is using 11 to 12 amplitube instances in one project. :D Your computer specs (you didn't touch on what CPUs those are? Amplitube may not be utilizing all cores btw, it is most likely using 1 cpu for all 12 vst instances. Amplitube in my experience takes more CPU than is necessary and I have had it crash in the past (in just one or two instances of the plugin) just from being a bit overloaded by surrounding vsts. If you are done with any of the tracks, Freeze them. You can recover at any time provided you don't accidentally delete the original recordings (which is hard to do if your project folder is where all the recordings are).

It shouldn't crash from multiple instances (while not running out of memory) unless there is some bug in Amplitube or Reaper. High CPU wouldn't cause a crash. I assume you are running the 64 bit version of Reaper and Amplitube and are or are not bridging? It shouldn't be crashing period if not out of memory. Best course of action would be to find the crash report in the Windows Application Event logs and paste it in it's entirety here. Just to confirm again, 64 bit Windows, 64 Bit Reaper, 64 Bit VSTs or some other config?

Thank you 

Thanks for the replies. I will post a crash report the next time it happens I have in this PC 8 Core AMD FX CPU 16 GB RAM 2 120 GB SSD WIN 7 64 bit Running 64 bit reaper, but not sure about amplitube. It does not give you an option to download 32 or 64 bit. Thanks again! -Matt

thanks 

I should be miking half of my guitar stuff anyway. Thanks again!

You can try setting Amplitube to run in a "Dedicated process", which will put each amplitube instance in its own process, and might allow you to do more of them...

Amplitube seems to place high demands on machines. I do all my recording on an old laptop with only 1gb RAM and I can't use it in more than one instance without problems. I can use other amp vst's like LePou, Freeamp or the Simulanalog one without any problem in multiple instances

I've ended up with almost as many Amplitube instances and 8 SampleTank instances in a recent project, and it would sometimes hang on loading in the way you describe. I'm afraid I can't offer any 100% verified advice, but I was docking all these FX windows in the docker, and if I made sure to close the docker window before saving, next time I loaded it was ok. If the docker window wasn't closed, it would quite often hang next time loading. Voodoo maybe, but it seemed to work :-) Jennifer