Kef Reference Tweeters-Ferrofluid Replacement

It took me three months to build up the courage to replace the Ferrofluid oil in my Kef tweeters.
There were several good videos on the internet how to go through the process, one in particular out of Texas. 
There were no videos or instructions which directly related to my specific speakers; Reference 3~2.
They are ~ 20 years old and I noticed that the highs were muddy and dull in the right speaker.
I run a Cardas Frequency Sweep record every 6 months or so.  The tweeter issue was noticeable during this maintenance procedure.
No replacement speakers (tweeters) are available from Kef or anywhere on the internet, so one wrong move and the speaker system would be worthless.  I felt like I was performing brain surgery.

First speaker took ~ 3 hours.  Second about 30 minutes.
I am happy to announce that the 'oil change' was successful!
The speakers are back to full factory operating specifications.
I've attached a link with some photos below.
If anyone needs to perform this procedure I can help walk you through the process.

Take care,


Showing 3 responses by ljgerens

A timely post for me. I have KEF Reference Model Ones and will shortly be replacing the ferrofluid in them. I did the ferrofluid in my KEF 104/2s previously and it was a very simple job. Took about 30 minutes for each tweeter. The Reference Model Ones seem a bit more complicated in getting the tweeter out. 
A couple of questions for Lou:

Does the NT25 tweeter just come out from the back side of the midrange driver assembly after removing that one screw in your photos?

Was the voice coil diaphragm attached to the magnet with an adhesive? If so, what adhesive did you use to reattach them?

Thanks for the info. Was there any adhesive holding the voice coil diaphragm to the magnet. On the T33 tweeters in my KEF 104/2s they had a thick double sided tape holding them together and it was reusable.
For 1 inch tweeters, you only need one 100ul tube for each tweeter. I purchased 2 tubes from Parts Express for my KEF 104/2s which have 1 inch tweeters.