Thank you to all who sent some advice!
My only previous tube amp was a Knight 24W mono that I got around 1956. I bought a University model 312 triaxial speaker and built a cabinet based on an electrovoice corner model that had a horn-like opening in the back coming from down low. To test it out, I carried the speaker out into the back yard, ran wires from the amp, dropped the needle on a 78 rpm Elvis record at high volume, and ran upstairs, got on my bike and rode a couple blocks to see how far away I could hear it. When I got back there was only the thump of the needle at the end of the groove and a bunch of neighbors standing around the speaker cabinet not knowing wha to do. I was like 13 or 14. Rock n Roll needed HiFi !