All systems go !
All systems go !
DRIVE UNITS BY MANUFACTURER:
FFAPG O87
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
Very easy to do on this model speaker as no soldering is required. Made a noticeable improvement. Well worth the effort and cost.
Has fixed the slight grainy sound on my old Mission 771s. The tweeter had a stain on the back suggesting the fluid had escaped. Make sure you release(unsolder) the coil wires before splitting the tweeter. Audax have replacement tweeters TM025C1 albeit 8 ohm which is another way to go.
Thanks for the review John!
Will & Caroline
Delivered quickly. 0.5ml is more than enough for two tweeters and the syringe is essential in order not to over-fill the gap. Well worth it - this has brought a pair of Mission 752 Freedoms back to life.
Thanks for the review Pete !
Will & Caroline
Friendly technical support
40+ years in the trade
UK family run business
Excellent customer service
Quick dispatch
I've needed something like this for years, fantastic product and a lovely company to deal with. Won't be my last purchase from them
It was a nice experience to send the old filters to the UK (from the Netherlands) and get them surprisingly fast back (taking the overseas shipment into account). At first I did it wrong since I also replaced the drivers that could also be connected in a 4/6 Ohm (double coil). But after correcting and calibrating my receiver the speakers sounded great.
Thanks!
Used in a DIY LS3/5a project, with Morel CAT 298 tweeters and custom crossovers using ClarityCap CSAs. Super pleased with these woofers! I think they synergize well with the “live” thin-wall LS3/5a cabinets. The sound is neither bloated, nor thin, just revealing, spacious, and with very lifelike tone. I’m so happy with the results of this project and had a great buying experience with Willy’s. Thank you!!
I used this in custom LS3/5a speaker enclosures along with Monacor SPH-135AD woofers and custom crossovers using ClarityCap CSAs. The tweeters have a very pure sound, revealing microdetails and having a naturally smooth, response. The sound is never peaky or rough. I’m very happy with my purchase and with the service from Willys. Would buy from again for a future project!
I bought a pair of Acoustic Research AR28LS speakers back in 1985 for £129 ! After about 15 years the foam suspension had started to perish and completely failed in 2006 following a rather loud teenage party. I was never happy with the Eminence Beta-8A replacements bought from a local shop at the time, as the bass resonance was far too high. Finally decided to replace them with Monacor SPH-8M and the speakers now sound as good as new. Arrived quickly and no problems fitting. Many thanks.