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Can someone please help ID this tweeter?

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Can someone please help ID this tweeter?

Postby mondayschild » 16 Feb 2017 03:40

Hello - I just picked up a pair of Magnavox s-8753 bookshelf speakers. They are a 2-way, air suspension design, probably from the 60s-70s. When I fired them up, I found that one of the tweeters is blown. That being said, the sound of the working speaker was quite nice. There is very little information on this speaker model, so I was not able to find anything out about how to replace the tweeter. The back of the speaker says that the diameter is 3.5in, though actual measurements show that it is really 3.25in. The spacing of the mounting holes is 2.75in. Can anyone help ID the tweeter so that I can do a proper search to find an original replacement? Or, barring that, could someone suggest a modern replacement that would preserve the "vintage" sound of these speakers? Thanks!
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Re: Can someone please help ID this tweeter?

Postby musicmn » 16 Feb 2017 23:35

Hi, probably the only way you are going to find exact replacements for this speaker is to buy another one that's in working order but may have cosmetic issues. Or you might get lucky and find someone on ebay that is selling the woofer and tweeter separately. What you can do is to remove the tweeter that is working and disconnect it from the wiring inside the cabinet. Then use a digital volt meter to check out what the ohm rating is. Then go to parts express and find a set of tweeters that have the same ohm rating and replace both. It's never a good thing to replace just one tweeter or one woofer, you will end up having unbalanced sound. I know you want to keep the original sound from these speakers but sometimes upgrading the tweeters is a good thing. If you can't find a set of tweeters that have the same dimensions then just open up the hole in the cabinet to fit the new tweeters. I hope this helps.
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Re: Can someone please help ID this tweeter?

Postby gofar99 » 17 Feb 2017 20:17

Hi It is quite likely to be a rather generic cone tweeter. One that is about the right size and likely similar in performance is the GT25 by Goldwood. Parts Express and Madisound carry them. Last time I got a few they were under $5. A great buy. Get two and replace both. It may be a good idea to check the crossover capacitor. Usually in systems of that vintage it was just a single non-polar capacitor in series with the tweeter. It might be bad and not the tweeter. If you can find it, temporarily jumper it and see if the tweeter makes sound. Do this at low power levels just in case the tweeter is good and the capacitor is not. You don't want to damage a good tweeter. If the capacitor is bad just get a replacement from one of the parts houses. They are pretty cheap.
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Re: Can someone please help ID this tweeter?

Postby mondayschild » 17 Feb 2017 22:54

Thanks everyone. I measured the good tweeter, and it came up as 8 Ohm. I didn't find any vintage replacements on eBay that I felt comfortable with, so I ended up going with the Goldwoods from Madisound. This way I won't worry about any sonic differences between the 2 speakers and they should still have a nice laid-back sound to them.
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Re: Can someone please help ID this tweeter?

Postby ynpguy » 17 Feb 2017 23:53

It was made by Alnico, for Magnavox, late 50's, early 60's. Yeah, replace both of the smaller speakers together.
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