Fostex: FE164 vs FE166en


2007-04-16 8:34 pm
I own a pair of Odeon Rigoletto speakers. The Rigoletto comes standard with modded FE164 drivers.... the mod is basically just the removal of the whizzers. I have also "Mod-Podged" the cones and added phase plugs fashioned out of small vacuum tubes. This might be too general of a question (without more info), but I am wondering if replacing the FE164 with the new FE166en would bring anything positive to the table. Does someone have any thoughts on the subject? Thanks for your help!


2007-01-24 2:28 pm
Hi robber222,

I have those same speakers! Speaking strictly as a newb, the biggest improvement was just disabling the tweeter and taking out the crossover, which it sounds like you've already done.

If you want to roll drivers, just be aware that the chamber volume needs to be carefully matched, and you'll be in "trial and error" territory unless you simulate the enclosure.
The drivers (FF165wk) are worked now about 30 hours.

Sounds well, but the sensibility i think is coming back.Rare behavior.

Is possible?

The sensibility is defined by the cone mass and the magnetic flux.The stuffing into the cabinet also, but ... i have no changes.

May be the reason is me: The influenza (gripe) don't allowed to my ears work well.Sure.

sensitivity change with driver use

The qts and fs drop slightly with use as the moving parts soften. They don't change enough to increase efficiency noticably.

E.g I got one driver from a set of four that is "broken", the magnet is undercharged. Qes is high, so Qts is 0.6 whereas the others are Qts 0.37 ...but the weak one is only 2.4 dB less efficient. The frequency response of the broken one is very similar too, with the good ones giving just a trifle more high frequency extension, and slightly flatter 1-2kHz

Break in of a driver has much less effect on the qts than this difference between a defective driver and a good driver. Efficiency change is barely measurable.
The drivers are now about 100 h work very fine.The not real sensibility problem was only me.The drivers work ever well.

May be the reason is the big time between the drivers production and live, but the FF165wk type at this moment is better ever as the venerable FE164 one.

Well stuff.Is the best FR 6.5 inch. than I tried... and cheap!!!

I'm very glad.

Dave and Bob...Thank's again.