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Do these 90s KEF Uni-Q Tweeters use ferrofluid?

absolve2525

absolve2525

Super Member
I have a pair of late 90s Q65 towers that use the poly cone/silk dome concentric with the oval race track woofer below it. Do these tweeters use ferrofluid? It's a 3/4 inch dome. I've never opened once up before. I plan to give these to a family member and want to make sure they won't blow from dried-up fluid, if there's any in there. It's definitely a tiny tweeter, from pics I've seen online. Thank you!
 

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I have similar, in some Q 15.2 speakers from that era, I believe they do use ferrofluid. I needed to send at least one of mine off for reworking when I bought those 2-3 years ago for cheap, as it was dead. I got the speakers for $60 and I think that's about what I paid for the tweeter fix.
 
The AK member who helped me with these was bigx5murf. Not sure if he's still active, mine had a broken lead as well as old ferrofluid. Removing the tweet from the woofer cone was pretty easy, as I recall.
 
Thanks for the replies. Hmm I wonder if it has dried out any yet? It it possible to check without destroying them? I've replaced the fluid on other tweeters, I'm just not intimate with this one.
 
I told my girlfriend that I was going to possibly open them to check the fluid quality, but she says they sound great and to leave them alone :dunno:. Midrange sounds very open and listenable. The highs aren't exactly in your face, so I boosted the treble a bit. I really do think they sound great, though. I am used to listening to ribbons and horn tweeters, so I think my ears are adjusting to the small silk dome sound. Can anyone share their assessment of how these should sound when working correctly?
 
Slightly old thread but seemed like a good place to pile on. I opened up a pair of NT19 tweeters today from a pair of 102.2 speakers. The ferrofluid was crusty and very dried out. The voice coils were almost stuck in the sludge. It wasn't difficult to pull the dome/voice coil assemblies out of the magnet side and clean them out. I use coffee filters cut into strips and wetted with acetone to clean the voice coil gap and the coils themselves using a Qtip. New ferrofluid and we're ready to go once the woofer surrounds are reglued. Fortunately the voice coils were still solidly attached to the domes. I've heard some folks have the VC's detach from the dome and were faced with either replacing the dome/VC assembly with new or regluing the VC to the dome. Should be able to get them reassembled soon and have a listen.
 
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One of the woofers apparently was bottomed out. The bottom edge of the kapton voice coil former was mashed and rubbing on the center post. I managed to trim it with a new Exacto #11 blade. It seems ok so I'm going to reinstall and try it. I've installed new foam surrounds on the woofers so if all goes well these speaker should be good for a while.
 
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