Vifa D19 ferrofluid questions

[jimk04]

I have recently pieced together a pair of Ruark Epilogues. I bought the enclosures and XOs off Ebay....I already had Vifa TC14 mids and I harvested the D19s from my old Mission 760.

I had reduced HF output on one channel. I wrongly diagnosed the tweeter itself. Turned out to be a bad connection in the XO

Well in my wisdom I assumed the problem was old ferrofluid so I dismantled the tweeter. The fluid wasn't thick and congealed but I blindly preceded to mop it out of the gap. Some had leaked out and was in places it shouldn't be IMHO.

So looks like I took out fluid that I shouldn't have.

The DS lists the fluid as AGP087 but this doesnt get any search results.

Are there other easily sourced fluids suitable.?
Tia

PS.....the Epilogues sound great....those TC14 I really like

 

[fatmarley]

Is this the tweeter? Vifa Peerless D19TD05-08 Tweeter - Willys-Hifi Ltd

 

[jimk04]

Yea that's the one. I have that window open in my web browser fully expecting to buy a pair as spares but these old Mission issue ones seem to be working well....or atleast one is me having wrongly 'modified ' one.

Cant say I can hear a big change in it although haven't given them much listening time yet

 

[markbakk]

I'd try the fluid Willys provides if I resided in the UK. Otherwise, speakerrepairshop.nl does normally supply customers with the right stuff.

 

[jimk04]

I found the same stuff as the Willys at Blue Aran for about a quarter the cost! Shall get some

Thanks

 

[system7]

This is a subject within my experience with SEAS 19TAF/G tweeters:

Buy it here in the UK at Blue Aran: Sonitus Audio :: Sonitus Audio FF05 PS4.99

As it goes, some of our leading lights are unconvinced of any real benefit:

I modify the grill and notch out the ultra sonic resonance. Then they are fine for the price.
The reason today Ferrofluid is not much used any more is that there are better ways to glue now that can stand more temperature.
Ferrofluid teeeters simply did not burn out as much so they had a reliability advantage.
On the other hand Ferrofluid can dry out and block the coil. I have seen that in the past.
There are also new, thinner types of fluid with which you can strike a compromise.

Michael Chua has messed around with it too: Ampslab Ferrofluid Experiment

My own opinion is they sound cleaner without ferrofluid. But use it for better power handling.

 

[jimk04]

Steve I happened upon your experience with the Seas tweeters just earlier today. I hadn't realised such similarities between the Seas and Vifa.

I read Troels had removed it from some tweeter.

Shall have a further read...thanks for the input

 

[markbakk]

As long as one realizes that removal and the different electromechanical properties do change the original HP filter slope. Now that's audible. And not only heat but dome excursion too is a limiting factor, so account for that when removing ferrofluid.

 

[system7]

The Morel CAT378 has ferrofluid but still an awkward impedance characteristic.

Michael Chua at Ampslab and myself both had a go at that one.
Finch (Morel CAT378 + Vifa PL18W0-09-08) – AmpsLab

By the best of my estimates, we need an LCR of 1mH, 47uF and 10R here. Plus a Zobel of 7.5R and 2.2uF. Mike got something similar.

Then when you use a single capacitor in front, it should behave predictably. Less of a problem with higher order filters, of course.

 

[boswald]

I have often removed ferrofluid from glued-together tweeters, as I'd rather not have to go back into them.


Just remeasure and adapt.