[font=trebuchet ms]Some metal players will tell you to crank the bass and treble while reducing the midrange (scooped mids), but the simple fact is that the guitar has it's voice in the midrange. Scooped mids sound OK playing on your own in the bedroom, but it turns to mush when your sound disappears into the bass lines.

For any style, you need to tailor the mids to suit. Jazz used to be built around dark, sometimes muddy guitar sounds, but I think there's more acceptance these days of guitar tones that 'cut through'. Bass at 10 o'clock, mid at 12 o'clock, treble at 12 - 2 o'clock. Adjust the levels for a clean sound, and add a smooth overdrive when you want some distortion.

My personal taste in blues tone puts the amp just on the verge of breakup, so that there's some headroom, while allowing some grind to add expression. Bass at 8 o'clock, mid at 2 o'clock, treble at 12 - 2 o'clock. A Fuzz Face or Big Muff tweaked for smooth warm distortion works well here. A lot of 'white-bread' blues uses tones that verge on metal, but I think that sounds ridiculous.

For metal, you need a tone control section that can shift the emphasis into the upper mids. With the bass set around 10 o'clock, the mids at 12 oclock, and the treble at 12 - 2 o'clock, (same as for jazz, actually) a lot of the tone comes from the levels set on the pedals and the preamp. Don't get carried away with the gain, or everything turns to mush. And too much treble will just make it sound harsh instead of heavy.[/font]