Don - Out of curiosity, is The Sentinel just a passive A/B/C/D/etc, or is it like those Tonebone pedals that can switch amps while they're on and hook them up to a dummy load?
Hey guys
Michael Wagener here. Just wanted to chime in.
First off, we had a great time working on these profiles with Don, could have not done it without him. I also want to shoot out a big "THANK YOU" to my engineer Gena Johnson, who did a great job on setting everything up with me, keeping track of all the profiles in the Rig manager and keeping me sane, all at the same time, Gena rocks!!!
The SENTINEL is a 2 in 20 out active/transformer-less switcher, made as a special one-off for me by Creation Audio Labs (http://creationaudiolabs.com/mw1studiotool/). I developed the MW-1 (!) studio tool wit Creation Audio Labs, a wonderful DI/Real-amp box (also without a transformer, it unanimously wins every single blind DI box comparison I do during my workshops at WireWorld, check it out here: http://www.creationaudiolabs.com/mw1studiotool). I don't record any guitars or bass without it, ever. So, I asked the guys at Creation to build me a switcher to access all my amps (or most of them) very quickly with a push of a button and also be able to switch polarity and ground source for each output. A guitar player has to fin HIS sound, but in the studio I have to find EVERYBODY's sound as quick as I can, so the SENTINEL helps me to switch between all those amps very quickly and to listen from the control room. It switches the amp inputs, not the speaker outputs. Like I said it has no transformers, so it does not color the sound, this thing is absolutely neutral. Creation is working on a commercial version of the Sentinel.
The setup you see is what I normally use during a recording project as well. We set up all the cabs with mics, so they are available for recording at any time. That does not mean that ALL the mics are used at the same time, even though they are ALL phase aligned and could be used together. I can switch which cab goes with which amp from the control room as well, using a Speakon patchbay, and though the combinations seem endless, I have found that certain cabs work better with certain amps, call it experience 
In recent projects I have used the Kemper on about 90% of the tracks, and only when I need something "special", that has not been profiled before, I switch on the amps. The KPA is THE best thing walking into my studio in the last 15 years, hands down!
A few more notes: I take the grill off all my cabs (except for the Jake E Lee cab from the Ozzy tour, like to keep that complete) so I can position the microphones closer to the speaker, and also so I can see the speaker without a flashlight. The Royer R-121 is my favorite mic for electric guitar, going through the Chandler Limited TG-2 mic pre at the 300 Ohm setting. Even though the R-121 can totally take the sound pressure coming from the speakers (and there is a lot of it!), it is better to keep it on a 45 degree angle to the speaker, so the air does not hit the mic straight on, but "runs down" the ribbon. I have never had a R-121 go down because of sound pressure, but it is totally possible to damage a ribbon mic just by just closing it's box too fast. I combine the R-121 with a LDC, mostly the ADK C-LOL series (http://hybridmic.adkmic.com/) and mix those two together to one track (or profile).
Hope this helps clearing up some of your questions. I am sure Don will post more pictures soon.
Cheers
Michael
