Bass head 1200 W mono / 2x600 W stereo. Impedance: 2 /4 /8 Ohm. Vacum Tubes: Preamp 3x12AX7, 3-band equalization. 7PRO pumps out a ferocious kilowatt of pure Ampeg tone in a compact design that weighs in at just 15lbs. The SVT-7PRO features the same professional features as the other PRO Series heads including a flexible 5-position mid tone control, remote switching FX loop and a sleek onboard variable compressor. The tube preamp boasts a premium JJ 12AX7 that feeds the weight-defying Class-D power section. Sure it’s portable and yes, it’s small…but it can power everything from a small single PN-115HLF up to a monster Heritage SVT-810E. And at 80 cents a watt, the value is undeniable.