I owned a Blue Univox UX-1501, bought it new when they first came out in the early 70's. I had seen an advertisement with Jeff Beck. Being a die hard Jeff Beck fan I had to have it. Unbelievable how many people it took to move it. No matter how loud you turned it up, there wasn't much break up. It took no less than three people to move the 6X12 cabinet that had Celestion speakers in it, We would have used 4 people to move the cab but there wasn't room for that. I recall paying $800 for the whole thing back then. The head was so heavy it was best to use 2 people, it had the handles on top. My gripe was there wasn't any reverb on it like cheaper later models but this was the top of the line amp. I had worked all summer to save up to buy the amp and I paid cash for it. A few months later I saw Jeff Beck with a transitional group: Bob Tench, Tim Bogert, Max Middleton, & Carmine Appice. He was using the same amp I had except he had 2 6X12 cabs. His sound totally sucked, all trebly and thin. Jeff went up to his amp after a song and twiddled with the knobs. It was loud and painfull. In middle of a song while Bob Tench sang, Jeff twiddled more with the knobs. After doing that another time he waved his hands at it in aggrivation and played on. Only on a few songs did it sound OK, mostly with slide guitar. When I got back home, I put my Univox up for sale and sold it at a big loss. I bought a new early 70's 50watt Marshall stack and was happy. Later I saw pics of Jeff Beck using a Marshall head on top of the Univox 6X12 cabs. To sum it up, it was: Clear, Loud, HEAVY, and Blue.