Although better known for their monster SVT amps from the late 1960’s, Ampeg made a family of electric basses that were quite unusual and advanced for the time from 1966 through 1969. There were four basic models, each of which was available in fretted and fretless versions.
The model designations are:
The letters seem to follow the following pattern – “AEB” means Ampeg Electric Bass. The “U” means Unfretted, the “M” probably means Magnetic pickup, and the SSB is the Short Scale Bass. In the late 2000’s, Canada’s Eastwood Guitars began to reissue two of these models, naming them EEB-1 (Eastwood Electric Bass) and EUB-1 (Eastwood Unfretted Bass). However, the re-issue simplified the headstock somewhat.
Here is a nice example of the original AUB-1. This one has had been modified with a modern bridge.