Altec 604E Blown Horn Diaphragm?

**chinacat** · August 28th, 2009, 09:21 AM

Hell Everyone: I installed my recently purchased Altec 604E's last night and one of them sounds amazing while the other one has no highs. There is sound coming out of the horn but it's muffled. I swapped the crossovers and it's not those that are causing it. Does anyone know the approximate cost of having this repaired? Any suggestions on who to send it to? Thanks so much for any help you can provide this newbie!---John

**just me now** · August 28th, 2009, 11:24 AM

Where are you located?

if you are in the US (maybe even if you are not)
Great Plains Audio (GPA) would be high on the list....

it seems as if it may be better to call them directly,
as opposed to emailing, from what i have read.

good luck!

**chinacat** · August 28th, 2009, 12:39 PM

I'm located in Central New Jersey. Any reputable companies in the NYC area that can recone the HF horn? What's the average cost to have this done? Thanks--John

**just me now** · August 28th, 2009, 12:48 PM

pretty much any reputable local technician would/should be able to change the diaphragm on it pretty easily...
(also consider that you may want to do both horns at the same time to ensure they better 'match')

the choices you have are to go with GPA diaphragms (as the 'sucessor' for all intents and purposes to the "Altec" that built your drivers), or an aftermarket option (like Radian or any other aftermarket offering)

the positive of sending it to an outfit like GPA is that they have the know how and facilities to really get the speakers up to factory spec -- specifically I am thinking of the degaussing machine to dis/re-charge alnico magnets if they need it...

most repair facilities do not have that type of machinery IME...

**bowtie427ss** · August 28th, 2009, 01:09 PM

Great Plains Audio's Homepage

Altec small format diaphragms were made to be easily field replaceable by the user. If you can operate a screwdriver with a degree of care, you can replace the phragm and install the conversion kit(necessary to install new style phragms) yourself. If your cabinets have removable backs, the entire driver can remain safely mounted in the cabinet.

Some instructions can be found here: http://www.altecpro.com/pdfs/vintage...r%20Repair.pdf

IMO, and IME, for any repair on Altec drivers beyond the scope of the end user's skills, GPA is the only source for competent service.

**oface1** · August 28th, 2009, 02:03 PM

I would go with GPA, especially with the whole degaussing machine they have, plus the experience in that place.......

But, I have interchanged the ones I have a few times. Like bowtie said, you gotta be careful though....

Good luck, and welcome to the board....

-chris

**Panomaniac** · August 28th, 2009, 03:46 PM

If you have your drivers remagged, have them measure the flux in the gap and tell you what it is before and after. Insist on this, it's important.

Enjoy those drivers, they will bring you a lot of pleasure!

**bfish** · August 28th, 2009, 06:48 PM

Originally Posted by Panomaniac

If you have your drivers remagged, have them measure the flux in the gap and tell you what it is before and after. Insist on this, it's important...

Why? If measured right after magnetization AlNiCo will be at saturation, and some meaningless value well above rating. 24-48 hours later they'll measure signifacantly less, though probably still above rating. Then after you hit them with decent power the first time they take another hit, albeit smaller, and will settle into their "groove".

**Mustang Marvin** · August 28th, 2009, 07:07 PM

Don't fool around unless that is just your thing. Go with GPA as I did and relax in knowing the drivers will be repaired as they should be and you can go back to listening. GPA is the best. You will see them mentioned time and time again here. If you what to fool around with measurements and opinions that's up to you. If you want your problem resolved and go back to enjoying your music the way it should be, Then send the drivers to GPA and forget about it. DONE...