View Full Version : Altec 12" duplex - poor sound - rebuild?

06-10-2008, 12:05 PM
OK, so I was looking for some possible candidates for two compact surround sound speakers for a 7.1 HT and came up with some slightly damaged Altec 617 - 8A duplex 12 inch drivers in 8 ohm trim on E-bay.

The items were correctly advertised as needing repair so, before I bid, I called GPA and asked them about the costs of repair.

When I recieved the package from the seller, I was pleased at the general build of the speakers that weigh about 18 pounds each. These come with external OEM x-overs and are trully beafy. From the frames, they look to me like circa mid 80s.

Anyway, so far, I have connected one to an audio source and was underwhelmed by its performance. Both HF and LF drivers work but the quality of the sound is very poor. The LF is thin and weak and the HF is grainy and shrill.

Question: Is it likely that a GPA rebuild will restore these to their former glory?

I thought that it would be rare that the sound quality of a home speaker would deteriorate significantly over time and that most repairs are necessary from distortion induced voice coil burn-out or physical damage.

What could be wrong;

1. bad magnets,
2. corroded voice coils,
3. mangled diapham,
4. bad X-overs,
5. crud in the VC gap?

If I threw these on an amp meter what would that tell me?

Since a complete GPA re-build may approximate 3 times the original cost for the pair, is this project worth it?


06-10-2008, 12:42 PM
...or, it could be that their intended application doesn't match your expectation.

Have you had a look at the spec sheet for this unit? :blink:

06-10-2008, 01:23 PM
...looked everywhere but never found specs. ...nothing on GPA cite but they told me via phone they have parts...

....So it is possible they built a 20 lbs duplex 12 inch in 8 ohms that was not intended to be a high fidelity driver? Yikes!

10 Watt Street
06-10-2008, 02:56 PM
Data Sheet at GPA:


06-10-2008, 03:06 PM
Data Sheet at GPA:


ACCKKK! 12" Duplex Ceiling Loudspeaker - its for Background Music - frickin' Elevator Music speakers!
"... mounting holes are provided on the rear of the loudspeaker to mount matching transformers ... operate the speaker from 70.7 volt distribution lines"

Yep, not High Fidelity at all!

06-10-2008, 05:17 PM
C'mon now, folks, from the curves, they'll mate with the 2370As in the mains quite nicely.... ;)

06-10-2008, 07:01 PM
The HF on those is an Atlas product per Bill H over at GPA, it was a second tier product imho. I am not sure what else the LF section might be other than a 414, but I do not think it is, I think Bill said it was unique, my memory fades but his is sharp and he knows and will tell if you care. You might consider listening to the LF section alone and seeing what you think, the graph on the HF is appalling, probably beyond salvage for HiFi, but great for WalMart.....

The 604 was also a ceiling speaker