Picked up an "Ampeg Bassamp" from Guitar center today. The tag said early 60's Ampeg amp. It has a Jensen 15 inch speaker in it and six tubes. It has two inputs, one for string bass and one for electric. Any idea on what the exact model could be? The Ampeg site has it pictured with amps from the 40's to the 60's. I would just like to know if there is an exact model number. The front also has a wooden horizontal bar splitting the speaker grill.