Help me ID this speaker.

[Axtman]

I recently bought an old Fender amp with the following non-original speaker. Below are the marks on the speaker. I can't find anything that resembles EIA codes. Please help me ID the speaker. Thanks.

580151-1
6920058
8-OHMS
28941
2857625

[Enzo]

285 is code for Rola, and 25th week of 1976 the date. SOund good?

[Axtman]

That sounds about right. Thanks Enzo!

It is a replacement speaker for that horrid trapezoidal Yamaha foam speaker in a Fender Bantam bass amp.

[Chuck H]

That sounds about right. Thanks Enzo!

It is a replacement speaker for that horrid trapezoidal Yamaha foam speaker in a Fender Bantam bass amp.

Is it trapezoidal?

Otherwise... My experience with a few non Celestion Rola speakers is that they sound pretty good, but usually aren't very loud. I did have one 10" that I really liked in a little combo I built because it sounded just right for that amp and volume wasn't the goal. Same with many old Magnavox "full range" speakers for guitar amps. Some others too I can't remember just now. I think we had a thread on alternative speakers for guitar amps here a long time ago. Rola was mentioned.

[Axtman]

The Rola speaker is just your traditional 12 inch coned speaker. The speaker that was originally in the Fender Bantam Bass amps were a funky foam trapezoidal speaker by Yamaha. There is lots of debate why that strange speaker was used.

[Chuck H]

The Rola speaker is just your traditional 12 inch coned speaker. The speaker that was originally in the Fender Bantam Bass amps were a funky foam trapezoidal speaker by Yamaha. There is lots of debate why that strange speaker was used.

I'm not personally familiar with that weirdo speaker, but I've seen the pictures and read about it some in the Teagle and Sprung book. It was a strange time for Fender, and amps in general

[g1]

The odd shaped speaker was used by Yamaha in their TA series amps. I'd imagine they somehow sold Fender on the idea for the Bantam.
This is what Yamaha had to say about it:

[Enzo]

Until I threw it out when the shop closed, I had a Yamaha speaker that was basically a 18x15 oval or thereabouts, except one corner was turned in on itself - like a bite was taken off the corner. Looked like an ear. It was originally used in a home organ model, and was mounted in front of your knees as you sat there. The odd corner was to make room for the expression pedal.

Here is what your trapezoids look like.
https://reverb.com/item/10164940-two...oidal-speakers

[Axtman]

There is a lot of speculation around the interweb as to why those wacky speakers were used. Nobody seems to know why. My theory is that Leo Fender (or CBS) got a great deal on those speakers from Yamaha. The Bantam Bass amp was the only amp with those speakers. I find it odd that Fender would have anything to do with a Japanese company. But the best theory is that it was 1969 and they were all high. ;-)

[J M Fahey]

285 is code for Rola, and 25th week of 1976 the date. SOund good?

Agree and add: those American Rola speakers were actually "Jensen made in another Factory"
Sometime in the 70´s Jensen 100% focused on their new cash cow: car speakers, and stopped making "guitar speakers" so they pulled all machinery, dies, etc, from the Chicago factory and moved them to the Rola plant, also owned by their Mother Company (I think it was Mutter something).

Leo kept using them, Fender labelled of course, black frame and zinc plated magnet plates instead of older Jensen colours but basically the same.

They actually sound quite good, were used in tens of thousands Fender amps to record great Music and nobody complained way back then, but they lack the magic label and Mojo and nowadays people listen with their eyes, after reading unholy Forums, so ...

I have measured them with calipers, compared to earlier Jensen ones, measured magnetic flux ... all the same

I can attribute any difference in sound to mid/late 70´s much heavier voice coils , wound on thicker formers , glued with Epoxy, and again glued to cone with a heavy thick ring of Epoxy which kills sparkle, compared to ultralight old voice coils, glued both to wire and cone with basically Nitro lacquer ... killer sound but couldn´t stand > than 20W RMS.

My point is that a Rola speaker is the ugly duckling, wholly capable of getting the Vintage Jensen sound ... if reconed with the exact same components.

As of the weird trapezoidal Yamaha speakers, I have tried them side by side with conventional speakers and Yamahas always won hands down: louder and cleaner big time , the better ones used advanced edgewound voice coils, had tight machining, etc; but didn´t handle much power (30W or so), so burnt easily and are ... ummm .... "unreconable" so disposable.

To boot they were OEM only so they quickly dissappeared .

But while they worked, they were very good.

[Axtman]

There is an electronics repair place in town that has that Yamaha speaker. I am debating whether I should try to buy that speaker and bring the amp back to stock.....or not. I am going to do further investigation to see if the baffle board is damaged.

The foam speaker makes me wonder if it was originally designed for outdoor use, maybe in a boat.

[Enzo]

Not likely. I suspect they found the material easy to mold to shape and control the thicknesses. A regular cone speaker would be deeper, so this takes up less room.

[Axtman]

Speaker in question. The magnet works!

[Helmholtz]

The magnet works!

Sure, why not?

[Chuck H]

Sure, why not?

He should have added a wink emoji since I'm sure he was just making fun that stuff was stuck to the magnet in the photo.

Americans have about as refined a sense of humor as Germans