Speakers for a Hammond organ

[punkykatt]

I just inherited a couple of 12" speakers that came from an old (1960`s) Hammond series K-100 organ. Im trying to find out who manufactured them. The numbers on the frame are 575546 and another number which i believe is their part number AO-24346-0. I checked the EIA codes and could not fine a match? Does anyone have a clue who might have made thes speakers?  Thanks for any help.  Punky

[Shrapnel]

575 = Heppner

a brand of speaker I am unfamiliar with.

[punkykatt]

Thanks Shrapnel,  They look to be a decent 15-20 low wattage alnico speaker. I have never heard the Heppner name before.  Thanks again.  Punky

[FYL]

I checked the EIA codes and could not fine a match?

Try this :
http://www.ecaus.org/engineering/sourcecodes.cfm

"Heppner Manufact. Co.

Round Lake, Illinois 60073
USA

Source Code: 575

Issue Date: 2/1/1981     Cancel Date: 10/27/1983
Comments: "

Hammond switched from Jensen to Heppner. Their drivers are very good, but should always be used in pairs : one is fitted with a light cone - trebly sound, the other with a heavier one - slightly muffled result. The pair gives a nicely balanced result.

[punkykatt]

Thanks for the link  FYL.  So those speakers were only made between 1981 and 1983??   I will have to take a close look at the cones to see if I can see or feel a difference. When I get a chance, I`ll have to put them in my closed back 2-12 cab and give a ear check.
Punky

[FYL]

So those speakers were only made between 1981 and 1983??

I'd rather say that Heppner's last avatar used the old 575 source code during that period.

I will have to take a close look at the cones to see if I can see or feel a difference.

One should be fitted with a ribbed cone, the other with a smooth one.

When I get a chance, I`ll have to put them in my closed back 2-12 cab and give a ear check.

I'd rather try them in an open back cab.

[punkykatt]

I'd rather try them in an open back cab

Why an open back?   I do have a Matchless 2-12 ESD cabinet with the original Matchless (branded) speakers which I cant get them off the speaker baffle, I think they installed the speakers before the paint was dry? Got any ideas how to get them off without messing up the gaskets or hacking up the baffle?

[FYL]

Why an open back?

Their Qts is quite high, going closed back would sound boomy.

Got any ideas how to get them off without messing up the gaskets or hacking up the baffle?

A flexible blade and lots of care maybe.

[softwarejanitor]

575 = Heppner

a brand of speaker I am unfamiliar with.

From my understanding Heppner was bought out by Cerwin-Vega in the early 1970s and the brand disappeared at that time.  Prior to that they were mostly an OEM maker and their speakers were used in things like Baldwin organs and Motorola Hi-Fi consoles  either unbranded or re-branded.  I've got a pair of Heppner 475 coded speakers that are labeled "Motorola Golden Voice" that came out of an early 1960s Motorola console.  I built them into a combo amp with a Motorola HS-475 tube amp chassis which came out of a different console.

[bigsbybender]

You may also find Rola speakers in Hammonds, but that code indicates Heppner.

and another number which i believe is their part number AO-24346-0

That would be correct.  Hammond's part numbers always have the AO- prefix. This includes speakers, proprietary capacitors, Potentiometers, Switches, etc.   

They also used the prefix for larger components as whole amps.  (AO-28 B3/C3 amp, AO-29, AO35 and AO63 to name a few.) 

j.