In the late 1960's there was an exterminator in Venice CA off Pico Blvd. His name was Frank Cooley. He built tube guitar amps. They were called "TNT". Canned Heat used them exclusively. So did I. I had a blues band with the brother of Bob Hite, "The Bear", Richard. We also had 125 watt TNT tube amps, all 6CA7 based designs. They came with 15" JBL's and they were LOUD!
The 125 watters were the small amps. The bigger models were either 250 or 500 watts. He didn't stop there. He built a custom head for Canned Heat lead guitarist Henry Vestine.
That one was 3 feet long, weighed in at 150 lbs and put out 1500 watts. It used 16 KT-88 power tubes and very large transformers.
It was used at one concert, at Santa Monica Civic in 1969.
Henry was SO LOUD people began to leave the concert. Frank was also there and flipped out. He began pulling out power tubes from the rear of the amp during the show.
In 1974 I was in West LA Music and that head was there right in the middle of the floor, for sale. I guess it was just dropped there as no one wanted to hurt themselves moving it. I thought about that $300 price, for about 3 seconds. Then I remembered the shear damage that thing could do. Once I did fire up the 500 watter in my parent's back yard in 1970. Ten minutes later I had a crowd of friends from 2 miles away all wanting to check out the rock concert. I had a 50 foot cord from my Strat and it would still feedback uncontrollable, too much even for me!
I memoriam to Frank, Henry and the Heat, I designed the Basson Sound guitar amps in a similar way. They are 120 watts, 4 6CA7 power tubes and enough SPL's to kill small rodents. I love them.
www.bassonsound.com