Oliver also borrowed a design from an old sewing machine where the unit would flip out of the cabinet.
Ampeg is a manufacturer of musical instruments, especially the musical instrument amplifier, established by Everett Hull and Stanley Michaels in 1946, and now headquartered in Woodinville, Washington.
This individuality is seen in a plethora of oddball tubes employed in the circuit, and some extremely versatile frequency-shaping capabilities in its tone stack and unique sensitivity and voicing switches.
The fiberglass body and unique design was key to projecting the sound of a double bass into an electric amplifier.
His idea was one of the many used by the Ampeg Company.
The 1964 side gives you a 25-watt cathode biased circuit, whereas the 1966 input features a 30-watt, fixed bias circuit.
Sonically, the 1964 side is spongier and breaks up earlier, while the 1966 input gives you a tad more headroom and midrange beef.