Hi guys, it's been a while, but I am in need of a bass amp to keep up with my band. I am a rhythm guitar player, but I am filling in on bass for a short time. I have a Peavey TKO 115 but it lacks the headroom to keep up without plugging in to the PA for rehearsals. Can you guys give me some size requirements, etc on what will work better? I'm struggling here because my little 18 watt Dr.Z is barely on and screams with guitar. I'm very new to this, so your advice is appreciated! Thank you.