Dried up Ferrofluid?

Hi b_limo!
Ferrofluid typically has a very long life span, but some of the older models of speakers are experiencing drying of the ferrofluid because the older formulations do not have the same long term properties of the new generations.  That being said, excess heat, long duty cycles at high voltage and dust and grime from decades of use will cause ferrofluid to gel and solidify.
There is hope!  The fluid can be replaced and it is not really that difficult to do.  Please contact me at vrene@ferrotec.com and I can walk you through the process.

Dumb question, do all tweeters have ferrofluid?

Dumb question, do all tweeters have ferrofluid?

No, you'll have to ask the manufacture if your does, it served two purposes, a way of getting heat away from the voice coil via the ferro fluid to the magnet which acts as a heatsink, also it served to damp"oil can" resonance at hf especially in metal dome tweeters.

Cheers George

Thanks George, I believe Thiel does in fact have ferrofluid per Rob at Coherent Sound .

pops
Thanks George, I believe Thiel does in fact have ferrofluid per Rob at Coherent Sound .

This correlates now with what many older Thiel owners are now finding and starting threads saying their speakers are harsh and/or have no sparkle. Their tweeter have lost a couple of dB’s and hf extension, and are now working very non linearly.

And this happens over time so you don’t even realize the tweeter performance is slowly degrading, and you enjoy your music less and less blaming your own age, your amps, your source ect ect

When all you need to do for $10 and a little labor-love is to clean out and change that ferro fluid in the tweeter.

https://www.speakerrepairshop.nl/en/instructions/replace-ferrofluid-in-tweeter/c-36

Cheers George