Hoffman Amplifiers Tube Amplifier Forum
Other Stuff => Cabinets-Speakers => Topic started by: Diverted on June 09, 2018, 12:30:53 pm
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Hi all,
The finer points of speakers are not my area. So if anyone can help me I'd appreciate it!
I have a bad 1959 Jensen P10R, an Alnico speaker. Pulled it and an identical P10R out of a trashed Fisher console.
One speaker works fine. The bad one shows good voice coil resistance (about 5 ohms) but I get no sound out of it. Just a very, very faint static-y fuzz sound, even with volume way up.
The cone moves up and down freely, so it doesn't look like anything is bound up. But what would cause a complete lack of volume with a good voice coil?
It's definitely the speaker, and not the circuit. I tried it on a few different amps with same issue.
If this does sound familiar to someone, what's the prognosis?
Thanks!
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Do they both measure about 5 ohms each?
Is it supposed to be 8 ohms possibly 10 ohms and you're only getting half or part of the resistance?
I don't know a whole lot about speakers either but between the cone and where you connect your wires is that braided wire connection good? I have had one with only a couple strands connected and kept the speaker from working.
That's about all I can head sorry I couldn't be more helpful. Good luck.
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Checking the web, the consensus seems to be that the issue is voice coil rub. This is usually obvious with a scratchy sound, but not always. Here's one guy's radical solution: http://www.antiqueradios.com/forums/viewtopic.php?t=126796
I googled: speaker fuzzy voice coil good
Maybe checkout some of the other hits there.