I know the rules and I've done searches, but i'd like to know how may watts i should have in this situation. I'm getting an amp soo, and want to do some small gigs around town. My friend and guitarist's amp is a 15w solid state, though soon he is moving up and getting a 30watt amp. I'm wondering how many watts I would need to compete with that, as the 15 watt practice amp i have now is getting hopelessy lost in the mix. I know the rule about (guitarist's watts x 4), so here are some amps that I've tried that sound nice, and could be a potential purchase. http://www.musiciansfriend.com/product/Marshall-MB60-60W-1x12-Hybrid-Bass-Combo?sku=483999 http://www.musiciansfriend.com/product/Ampeg-BA115T-1X15-100-Watt-Bass-Combo-Amp?sku=481724 http://www.musiciansfriend.com/product/SWR-LA15-Bass-Combo-Amplifier?sku=482038 I have about $600 to spend. Thanks to anyone who helps.