Vintage Ampeg B15-NF speaker replacement

[Rutherberg]

Hi,

I have an Ampeg B15-NF on the bench, the speaker has an open coil.
Which replacement speaker would you recommend to keep the voicing as close as possible to the original ?

Thanks

[catalin gramada]

There are two popular replacements among the users: beta 15a and delta 15 (better pro 15a version) from Eminence. I didn.t own a portaflex but used both speakers in 3cf cabs and beta have not the high mids enough for a good bass guitar presentation from my point. I think a EV15B will be a nice replacement too if you find one in good condition.
Be aware at the size of magnet if you store the amp upside down in cabinet. I think this is the biggest problem which limit the choice of speakers you may use...
This is my RJ type cab project I built years ago, pretty similar as principle and internal volume as portaflex is, used to test beta 15 and delta 15 from Eminence:
The second baffle slide in front of speaker baffle by easy 4 screw adjustments to easy tune the RJ type port.( I remember portaflex used some rubber pipe pieces in between to tune the port...)

[Rutherberg]

Ok, thank you for your feedback.
I forgot to mention, the amp will be only used in studio, if that matters

[glebert]

Is recone not an option for this? I have no idea if the materials are available, but it seems a recone would be preferable if possible.

[The Dude]

Also check tinsel leads. It could be as simple as a broken lead.

[Randall]

I put an Eminence Beta 15A in mine. I like it better than the stock square magnet speaker from the factory.

[Rutherberg]

Thanks for your feedback.

Also check tinsel leads. It could be as simple as a broken lead.

Checked it, seems ok. One time I had the case of a burned tinsel lead, it didn't measure open but it was enough to impair the sound.

I think I'll go with the popular opinion, beta 15A is often mentioned, I'll try that !