I'm assuming we are going for huge, mean distorted electric guitars. That means we'll want layers. We'll want to double the guitars at minimum. Seldom do I go over 4 total layers of rhythm guitar unless I'm going for something weird.

Assuming the guitar player has a crappy amp (which stands to reason that the player may also be crappy), we'll use one of my amps. Generally speaking, the Rivera Knucklehead or Marshall Superlead 100 watter from 1971 are my first choices. The Rivera is a little more flexible, but the Marshall does something special. The 5150 will sneak his head in there from time to time as well, but isn't always my first choice.  There is nothing wrong with the 5150.  I've just had easier luck getting what I wanted with the Rivera and Marshall.

If I'm working with the Rivera, I'll have my JCM 800 4x12 cabinet loaded with Celestion G12H30 30 watt speakers in my guitar fort. I'll stick a Royer R121 ribbon mic on dead center of my favorite speaker. (Yes, the same model speakers always sound drastically different). If I'm using a Shure SM 57, I DO NOT put it in the center of the speaker as the result is way too bright / fizzy.

I'll start with the amp's volume on 10. Yes, that's right, I don't waste time. I like power tube distortion. That's the end of it. So I start with getting as much power tube distortion as an amp has (within reason). I also start with the low end on zero. Depending on the guitar used with it, the Rivera Knucklehead does something crazy with the amp's volume on 10 and the low end on 0. The low end is often HUGE!! Huge, but not in a dumb, undesirable way. More like in the way that you really hear on huge guitar records. The low end is not muddy or excessive. The power tube compression keeps it from getting too out of hand.

If I need more gain than what the power tubes provide, I carefully add gain with the pre-gain knob. This seldom gets over 2 or 3 since the power tubes are doing the work.

I keep my mids pretty high on my amps. It's rare for me to record with the mids below 6 and I don't hesitate to put them on 10 even for metal records. The high end I have to be careful with. I'd rather record a little dark than risk ending up with a fizzy guitar track. If I'm using a 57, I'll go a little dark on purpose. If I'm using a Royer R121, I can get away with quite a bit more high end as the ribbon seams to ignore a lot of the fizz.

After I've got something pretty close to what I want, I grab my vintage MXR 10 band guitar EQ. I put it in between the guitar and the amp. I almost always bump up 1Khz a nice healthy amount. Sometimes I cut the lows out a little bit. For the most part, guitars have a place in the mix. It's the mids. Even albums like And Justice For All have quite a bit of midrange content in them even though people talk about super scooped mids.  (If you want to hear super scooped mids try one the DOD death metal pedals or a Boss Metal Zone.  Neither of these have anything resembling the tone of any record I can think of.)  The problem is the word "midrange" covers A LOT of frequencies. 3Khz is considered midrange but is more like the high end of a distorted guitar. So, while And Justice For All is definitely scooped when compared to something like Iron Maiden's “Number of the Beast”, there are definitely a lot of mids in that recording when compared to something like a Boss Metal Zone.

If I'm recording mega metal, I'll still boost the mids up in front of the amp, but I may take them back out on the amp itself.

I also like to use an impedance matcher that I picked up when I was down in Nashville. It's a subtle thing, but it does something I like. It's called the Redeemer.

This is my basic approach. I adapt it to whatever I'm doing, obviously, but this rig has worked fairly well for me.