Ampeg BA115HP

[Mack C]

I have the above amp and it is in the shop having a transister replaced that caused the speaker to fail. I am wondering if anyone knows what the original speaker might have been for this amp. What is in it now is a Celestion BN15-300S. I can get that speaker and I am trying to decide of that is the right move or if I should go with a little better speaker.
The other option I am considering is putting (2) 12" speakers in the amp in lieu of the (1) 15". Any thoughts or advice would be helpful. Thanks

 

[BogeyBass]

Ampeg used a 4 ohm 15" Eminence
Just pretty basic stamp steel driver.

86-118-04
Is the Ampeg part number
150 watt speaker with 2.5 inch voicecoil

Finding 4 ohm 15" is tricky
Likewise usually a 4 ohm coil makes effciency drop. Say a typical 8 ohm is around 96 to 98 dB

4 ohm coils can drop to 94 to 96 dB

CA154 from Eminence is a Equivalent
Driver 4 ohms.

Eminence also makes the
Delta 15LF-4

Same metalwork/ magnet different cone and voicecoil.

15LF-4 has a lower resonant frequency and slightly higher xmax.
Takes a Efficiency drop of 1dB for extra power handling. Works and designed for smaller boxes

If 2 x 12" speakers fit in the baffle sensitivity would go up alot. Plus it would use standard 8ohm coils in parallel for 4ohms.

Assuming the airspace is 2.8 to 3.2 cubic feet for a single 15"
That would leave 1.4 to 1.6 cubic feet per 12". It's on the small side for a 12" which prefer 1.6 to 2 cubic feet per driver.
So it would be a pair of 12" that does well in a small box.

The Beta-12CX is a coaxial driver designed for very small monitor wedges.
So would be a good candidate. You would just use 2x drivers and plug the coaxial mount on the magnet.

 

[Mack C]

Thanks for all the information. The tech sent me a picture of the speaker that is currently in the amp and it is a 8 ohm speaker so this may not be the original speaker. I had downloaded the owners manual for this amp and it appears that this amp, the 220 watt output version, was made in a 115 version and a 210 version so maybe (2) 10" speakers might be a better choice rather than (2) 12" speakers.