thanks a lot guys. I was definately planning on getting a half stack, but its not a reality before this concert (it's this saturday).

Another question; if I'm to mic the amp, can the mic go right to an ext. speaker? or will I need a pre-amp, or mixer first?

Should the amp be low to the ground, mid-height, ear level?

Where should I mic the amp? I've always close miked it for recording, but would that work well in a live situation? Or would it be better to keep the mic a little off?

BTW my current EQ settings are (the typical METAL settings)

Bass:10
Mid:2
High:8

then my amp has a PRESENCE: 6
and something called "T. Dynamics", I ahve no clue what that is but it sounds good at 100%.

I was so pissed today cuz in the garage it sounded wonderful, and at the gym it sounded very nasally....

keep the advice coming please ;)