B-15 September 1960
B-15 September 1960(top)
Although have similarities, there are several distinguishing visual features that sets the earlier B-15 from the B-15N. The B-15 is dressed in what is called random navy flair vinyl. This is a basket weave material with a sparkle. The grille cloth is different from the one found on the later amps. The chrome chassis is cradled in an amp tray that has sides that are higher than that used on the later models.
These amps are quite rare. James Jamerson was a notable user of this model.
The middle input jack is labeled stereo. It links channel 1 and 2 together for use with the Ampeg string bass acoustic pickup. Make no mistake about it, the B-15 was designed for use with a string bass. Both Jess Oliver and his boss and Ampeg owner Everett Hull, were string bass players. Ampeg didn't even have a Fender bass, what electric basses were commonly called at the time, on site for testing these amps.
Note the combination power, standby, and polarity switch. A functional and pretty neat idea. There is also a jewel light, something that the B-15N didn't have. There are two volume controls but only one set of treble and bass tone controls for both channels on this revision.
The stereo input jack in the center. Channel 1 and 2 are still available for use separately.
The Ampeg script logo is very delicate on vintage amps. It was made of chromed pot metal and they get brittle as they age. These are often broken.
The side handles were unique. The panel on each side could be removed to change the porting of the cabinet to better suit the needs of a string bass.
Octal speaker connector plug and socket. This isn't a locking connector like the ones seen on the B-15N's. As a result, they are easy to pull out by mistake if the speaker cable is stepped on.
Two screws on each side attached the chrome chassis to the amp tray.
Note the classic knobs that were common on radios and Test equipment at the time.
A Jensen ceramic P-15N speaker, rated at 20W. In 1963 Ampeg later used the heavier duty Jensen EM-1500, a 60W speaker.
The removable side handle panels that could be removed to change the cabinet's porting for string bass.
The serial number indicates the 9th month of 1960.