#1
I'm having my first gig with the band in a few weeks. I currently own a spider III 15w.

(When I got it I didn't realize what tone was and its just for practice)

Now I was thinking of borrowing an amp from a buddy, but all of them have practice amps like me ):

The best one out of all them is a 75w Spider III (same as mine but bigger).

I don't like it but I think its my only option. If mic'd will that be enough for a small gig?
"When the power of love overcomes the love of power, the world will know peace." - Jimi Hendrix (R.I.P.)

"I'd much rather be home playing my guitar"
-Eddie Van Halen
#2
Yes, it will be loud enough. It just won't sound all that great.
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(512) Audio Engineering - Custom Pedal Builds, Mods and Repairs
#3
It will work.... just know you will want a new amp ASAP
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