So when my band practices, its usually me and my bassist plugged into my 75 watt amp together, since his cable broke on his amp, which already worried me a bit, when i practice we play at about half the volume. But we just got a new singer, my amp has a microphone plug built into it, we'd still be playing at that volume, but 3 frequencies coming out at once scares me, also we're playing our first gig, but they'll have a PA system, but its still me and my bassist at about 3/4 volume... Would any of this have a good chance of blowing out my speaker??