Not trying to sound too much like the tube amp snob that I am, but I wouldn't waste your time with the SS crate amp (ok, I didn't try very hard did I?) Actually, I suspect there are tones that could be had from the crate that you might like, but I've never heard a SS amp that sounded good to me for what I like.
As for what I think you are looking for (and I think I know what you are saying), unfortunately there isn't much in the way of a solution that isn't going to be really loud. I'm interested in Greg's comment about more layers. I think know what he means but I won't try to explain that because I may be wrong and I haven't done it. He's totally right about less gain, though. Typically as guitar players we want to crank that gain knob and get lots of sustain and grunge and so on and so on. Unfortunately when you record that sound it just comes out like mush. What the gain knob is doing is overdriving the preamp tubes. Typically with modern tube amps there is also a master control that let's you turn the signal back down as it heads into the output stage so you get a preamp distortion sound at a reasonable volume. It's not a bad compromise for messing around, or even for live stuff, but when you record it, it just doesn't sound like the real thing... cause it isn't. The kind of distortion that really sounds and feels good (and records well) comes from overdriving the output stage and yes (to some extent) the speakers. With the classic amps from back in the day, there wasn't a gain/master setup. That's because they weren't originally intended to be overdriven at all. The classic distorted sound we know and love came about as guitar players turned these amps up to their max (where the designers never imagined anybody would want them). The result (at least in the amps that became famous) was saturation of the output stage and that warm, "dirty but clean at the same time" kind of distortion that there's really just no other way to get.
What exactly is your amp? You say Fender Music Man... Is it a Fender or a Music Man? I don't know of Music Man as a Fender model, I do know there was a Music Man company that made amps. I think Leo Fender worked for them at one point, so maybe that's what you mean. Anyway, do you know what circuit it's based on? You say twin reverb. I know that as a Fender amp, but maybe there's some connection to Music Man I don't know about. Anyway, the question is whether you have a gain/master setup or not. Could be called drive/master as well, or who knows what else. Whatever it is called, if you have it and you want a really great sound... Put your earplugs in, turn the gain all the way down, crank the master all the way up, plug in and start turning the gain up. The tone will go from painfully bright and clean while its quiet to, clean and punchy as it gets a little louder. At some point as it gets reaaaaallyyy loud, it should start to break up and sound overdriven. Somewhere just into this breakup is where the best tones are going to be, more or less depending on just how distorted you want the sound to be. Just remember it will sound more distorted when you play it back than it did while you were tracking it.
Books have been written on mics and mic placement. I like an SM57 about a foot away from the speaker about a third of the way from the center of the cone to the edge of the speaker. I like the sound better with the amp up off the floor and about 8" away from the wall (I can't say I've actually played with the distance from the wall part, cause about 8" is just what I've done. The other things I have played with all different ways and like this setup best).
I hope there's no max quota on characters here. It seems I tend to ramble a bit. (That's what the scroll bar is for if your eyelids start to droop.)
Now, if your amp doesn't have a gain/master setup (a twin reverb doesn't), you are going to need one more thing: a drive pedal of some sort. The process is the same as above. Crank the amp WAAAAAAAY up, with the pedal waaaaay down. Then bring the pedal output up gradually til you get the crunch you want. Twin reverb is (I think) an 85W amp, so it's going to be un-freaking-believably-loud, but it sounds fantastic (I've never owned a TR, but I played a gig with one once. Very nice amp-chimey and bright, but louuud!!! Very nice tone when driven.) There's loads of debate around what pedal to use. Most pedals are designed to create their own distortion, too, which you don't want much of at all, so use the same process as with the drive/master controls on the amp. Turn the output control of the pedal waaaay up and the drive or gain control waaay down, then turn up the gain knob til you get the loudness of the amp up to where it sounds good. Which pedal you use and tweaking the gain vs output on the pedal can change the character of the sound. That's a taste thing. Stevie Ray Vaughn played TS808. That's a great pedal. I have
a Boss OD1 which works well for me (almost the same circuit TS808). People will talk a lot about the OP amps in the pedals, but I think that's a bunch of baloney. Different circuit = different sound, but different chip? nah!
Anyway, last thought. If you try this and like it but worry about raising the dead or having the neighbors call the cops, there are two solutions. First you can buy (or build if you are industrious enough) a power soak. This is a circuit that sits between the amp and the speaker. It loads the amp down exactly like a speaker would, so it let's you operate the amp at high output where the tubes sound good, but then it only passes a fraction of that power to the speaker, so your ears don't bleed, you lose some of the speaker distortion, but that actually peaks at a lower volume than the power stage saturation for most amps, so that's not a bad thing as long as you still get the volume up so the speaker still... speaks
.
The other solution (and my preferred one) is to get a lower powered amp. Clapton recorded with Cream playing 100W marshall amps cranked to the max. He recorded with Derek and the Dominos playing a 5W Fender Champ. It's not about the volume, its about exercising the output tube, transformer and power supply (and having a good speaker - if you look at a Champ or say the Epiphone Valve, Jr., you MUST connect it to a decent cab. Sounds like crap through the built in speaker). I built myself a clone of a 59 Fender Deluxe, with a footswitchable TS808 circuit builtin. It's an 18W amp, so it plays loud enough to gig with, but quiet enough that I can crank it and not strip my eyebrows off. I can't say I recommend the Champ or Epi Valve Jr as anything other than recording amp. I didn't buy one for exactly that reason (although I may build one!).
Last, last thought. Old amps sound great cranked all the way up. They weren't always designed to be operated that way, though, so I take no responsibility should anything go pop... sizzle... bzzzzz. It is very unlikely that it will if it's a decent amp in decent condition, but I just figure I should throw in a little disclaimer on that.
Good luck,
J
PS (He's not done???) - Greg probably means more than this by his layering comment, but at a minimum for a rhythm guitar part, record it twice, played as nearly the same each time as you can. Then pan one left and one right to give the part some width.
