1. Time for some upgrades in server hardware and software to enhance security and take AK to the next level. Please contribute what you can to sales@audiokarma.org at PayPal.com - Thanks from the AK Team
    Dismiss Notice

B&W CDM1 SE Tweeter ZZ9989 Ferrofluid Replacement?

Discussion in 'British Audio' started by JamVal, Jun 18, 2018.

  1. JamVal

    JamVal Super Member

    Has anyone here replaced the ferrofluid in the B&W ZZ9989 Tweeter (ZZ4723 Tweeter Assy)?

    I recently purchased a set of CDM1 SE's and the tweeters are working well. Since these are around 25 years old I'm considering replacing the ferrofluid. I have read through this article ( https://www.speakerrepairshop.nl/in...eeter__zz09989___zz9989_&lang=en#.WyeuKfZFzIU ),
    but have a few questions for someone that has actually done it:

    1. Removing the diaphragm: The article says it is clamped on the magnet. Any tricks to taking it off, or any risk of breaking the diaphragm mounting plate which looks to be made of plastic.

    2. Since my tweeters are working, I assume I don't need to replace the actual diaphragm dome and coil, correct?

    Thanks for any tips or tricks in doing this.


    Please register to disable this ad.

  2. slimecity

    slimecity Super Member

    New Zealand
    I dont have these tweeters but have recently redone the fluid on 4 x KEF T33 tweeters.

    Replacing the fluid should be done as a maintenance issue - if you can - try to get the same viscosity rating the manufacturer used (this can be difficult).

    There was a definite improvement in sound once I did my tweeters and you will wonder why you didnt do it sooner.

    No you wont need to repalce anything else including the diaphragm dome and coil. However in a worst case scenario where fluid isnt replaced - the dried out fluid can act to clog up a tweeters VC movement - turning to sludge and preventing the VC from moving -this can tear the diaphragm or cause the VC wires to break. Hence its a good idea to replace the fluid!

Share This Page