Size of Midrange Drivers

Duke, midrange drivers in my speakers use ferrofluid suspension instead of spiderweb (to increase speed by lowering overall mass). Coils are oversized connected to flat ring that holds membrane (instead of dust cap).

http://www.enjoythemusic.com/superioraudio/equipment/1104/hyperionhps938.htm

I assume that oversized coil in ferrofluid has low thermal compression. I'm only worrying that ferrofluid will dry out one day.

The largest cone midrange I can find is in the Tannoy "Kingdome Royal" speaker.
It uses a "12in Dual ConcentricTM drive unit" with a tweeter in its center.
Now we're talking (where did I put that Tool CD?"!

Kijanki,

Do you know who makes good ferrofluid suspended drivers like the ones in you Hyperions - or better yet, the ones found on your speakers? I'd like to learn more for a DIY project.

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FWIW, back in the "slopped baffle" thread Roy Johnson from Green Mountain Audio made several points about driver size and selection. He mentioned he used a 4.5" midrange driver for his Calypso as it was designed to work in living rooms and audio rooms, but he used larger drivers when designing speakers for vary large rooms. So I wonder how much of a concern is beaming for him, as it would seem the detrimental effect of beaming would be more notorious the larger the room.

Good thread!

As well as bombaywalla tried to explain it, I think dweller is still confused.

Shakey

Have a loudspeaker that I'm working on with 14ft long horn 43x62in bell 4in compression driver used as a mid range.