2 amp set up!!

I'll lend a helping hand here (love your sig name BTW).  Okay I'm assuming both of the amps are heads?  So step by step here's what I would do...

1) You will need a STEREO cab.  There are plenty of them out there but unfortunately most of them are 4x12s.  Being that your Marshall is 100w you will likely need a 4x12 cab.  Another option is to buy a Marshall 1936 cab and put EV12Ls in there.

2) You need to have a really good amp selector ABY pedal to avoid phasing and ground loops.  Voodoolab makes a great one, as does Radial.  Joe also highly recommends the Lehle units and I also believe he uses the ones by Palmer.  Most of them are going to cost you around $200 so suck it up and drop the cash on a quality one. Ground lift switches are a BIG PLUS.

3) You need 2 speaker cables (duh)

4) Pedals and pedalboards...  You have to figure out which effects you want feeding one or both amps.  If you want an overdrive to hit both amps you must place it prior to your amp selector.  If you want it to hit one for example Joe and his Fuzzface/Superlead, you must run it after your amp selector and into the specific amplifier.  A great Joe Bonamassa survival kit would include:

a) Tuner- I like the Planet Waves or Korg ones.  Peterson Strobostomp if you have crazy money to spend on a tuner...
b) Wah - Hard to beat a standard Vox wah for tone and value
c) Tubescreamer - TS808 RI or TS9 on a budget.  I also highly recommend the Fulltone Fulldrive 2.
d) Fuzz - run this to your "variable amp" (Supersonic).  The Dunlop Hendrix Fuzz is cool, and I also like the Tonebender stuff out there.  The Fulltone Catalyst is a pretty sweet pedal and very tweakable.  Also the Octafuzz has some gnarly fuzz tones.
e) Delay-  Boss DD3 for digital or Ibanez AD9 for analog on a budget.  Both pedals sound great and are very reliable.  Also if you need a bunch of different delays the Line 6 DL4 is pretty good.  Run the delay through the effects loop of the Marshall.
f) Reverb- Your Marshall has some which helps but you may need some for the Supersonic.  I like the Spring Chicken reverb or the Fuchs Reverb unit.  Also Joe recommends the Boss Reverb pedal.
g) Chorus- you don't need anything really fancy here.  A TC SCF would be nice but they are so expensive.  I just picked up an Ibanez CS9 and it sounds very very good.  The Boss Chorus is also decent on a budget.  I'd run the reverb/chorus through the effects loop of the Supersonic to create a width and "spread" to the sound.

So lets recap:

Marshall DSL- Green Channel mild crunch overdrive.  Slight reverb dialed in with the delay in the loop.
Fender Supersonic - Bassman or Burn channel set for moderate overdrive and sustain.  Think smooth Dumbley or Robben Ford type tones.  Also the Reverb/Chorus pedals in the loop of this amp.
Tubescreamer- boost both amps

That should get you close to what you are looking for.  I hope this post has helped.

WOW!! THAT IS WHAT I NEEDED! I CANT THANK YOU ENOUGH.   

YOU ARE NOW THE GODFATHER OF THIS FORUM!!!

If your Supersonic is a head you are going to need another cabinet.  If its a combo then just use your marshall and the 2x12 and the combo sitting next to it.

I agree with most of StratPaulGuy's notes.  They are an accumulation of probably 40 threads on this site. 

There is another option though.

I run my guitar into a tuner -> wah -> Fulldrive 2 -> Ocean Effects TD -> then to my delay.

From there it goes into a Whirlwind ABY splitter.  80 bucks I think at GC.  I run channel A into a Fender 100 watt twin, and Channel B goes into a delay pedal into a Vox AC30.

You dont need crazy ABY switchers and ground loops and lift switches.  I have never gotten shocked no matter how I plug my rig in. And my rig is not loud when I am not playing.

If you have endless money out the wazoo I would follow the Joe B survival kit to the T.  However if you are strapped for cash you dont need to go crazy.

Get a whirlwind ABY, Arrange your pedals how you like them keeping to StratPaulsguys recommendations for where to put your overdrives. 

The easiest thing I have found is find overdrives you like the sound of when your amps are clean.  That way you use the overdrive for what its designed for and you can always control your volume without affecting your tone. I dont like being in a position where I feel like my volume needs to be at 9 to be happy. The places I play wouldnt allow me to be happy much. Neither would my band.

Good luck though.

Keep us posted on your results.

I would highly suggest this fairly cheap option.  Go buy two mics you like... sm57's or what ever... run both of them into a small personal mixer.  Peavey, Mackie, they all make small little 6 channel or 4 channel mixers.  Then when the sound man comes up to you give him a mic cord that is an out from your mixer.

The only issues are YOU need to have your mixer set with the balance you need or like. The soundman cannot pan one guitar left or right or make any adjustment other than total volume.

If your in a small band that does small bar shows and you need to mic your amps and you dont have a dedicated soundman who knows your band... this is a simple way to be consistant. You need to soundcheck your self very carefully before each show to get your amps in balance so its pleasing to your ear. You may have differences in the rooms and the equpiment that is used by the venue. So you might need to add or subtract a little of which ever amp to make it sound good.

Otherwise you are stuck having to hope that soundmen have two mics for you.

I never assume Sound guys have anything I need. So thats why I like this system. All they need is a mic cord that goes to their board.

I've used this method at churches where they are fanatics about micing amps and if you can even bring amps.  I've been told that I need to run my guitar directly into a direct box.  Needless to say that didnt happen but they seem to think they know everything there is to know about sounding good.

That said it goes a long way if you have a rig you really want to play thru if you have everything set up and you can just give them a mic cord and say just plug this in and everything will be ok. Usually after I do that they are willing to try it and I've never been told sorry thats not going to work.

But here is the main reason why I use clean amps with overdrive pedals. I play in bars too but for either gig I can simply adjust the volume on the amp... but I am not limited by needing to crank my amps.  I can get my tone at almost all the levels above 2 on the twin and 2.5 on the vox. If I needed to crank my amps to be happy with the tone I'd never be happy cause I'd have to build a cabinet to store the amp in while playing so that the church or bar wouldnt get blown away everytime I play. There are enough overdrives now to find ones I like that sound great. Thank God.

No one has ever paired a 5E3 with a Marshall 18 watter?