Tina Turner 1939-2023



Ferrofluid Tweeter Repair Kit

For restoring old tweeters.

APG O87, an ester based fluid with a saturation of 250 Gauss and a viscosity of 750 centipoise. Manufactured by Ferrotec USA .

Other available formulations, contact us for details:

CDF 2250 (Ester based): 220 Gauss, 500 cP

APG 1134 (Hydrocarbon): 220 Gauss, 1000 cP

There is over 100 grades of ferrofluid; the above are the most common specific fluids used by major drive unit manufacturers

Beware: some unscrupulous sellers are offering the cheap, commonly available science project type ferrofluid as an audio product. This results in an unpredictable / overdamped output and can soften drive unit adhesive - always double check the origin and the specification.

Ferrofluid is a cooling / damping compound used in the magnetic gap of many tweeters to increase power handling and smooth out the frequency response; it has a tendency to thicken with age, gradually reducing tweeter output to zero. Many old tweeters from the 1980s/90s can be restored to perfect working order by carefully dismantling and cleaning out the old coagulated fluid then replacing with fresh.

This refill kit comprises a high accuracy syringe pre-filled with Ferrofluid specifically formulated for high fidelity tweeter application. There is sufficient in the syringe for 2 tweeters & a micro applicator nozzle is supplied.

Willys-Hifi Ltd, the UK speaker specialist.

Helpline 01702 523999