I recently got 2 Ampeg Classic Series SVT-15E's. I plugged in my SVT and thought it sounded thin. I know that the stock speakers in these cabs only handle 200w but still thought it should have sounded better than it did. I took my GK MB500 and hooked it up to both cabs individually and they both sounded great. Could I be experiencing a phase issue with these cabs even though they are identical?