[Ryerse Rocks]

I am thinking of constructing a simple bass reflex small speaker using the FE87E driver. The plan for the speaker is furnished by Fostex. I will be using it primamirily for background music. Has anyone built this speaker and/or has any experience with it?

Thanks

[JLM]

Let us know how it goes/sounds.  It'd be nice if it got down closer to 80 Hz to meet HT standards and work better with a sub.

[planet10]

I looked at FE83, FE87 and FF85 to build a small speaker. I choose the FF85K because the other 2 require a box as big as the mFonken which uses FE127.

We haven't built the little box yet, but slapped the (modified FF85 in a little OB,  No bass as one would expect but everywhere else it is very good.

The little box will be 2 litre and sims to just below 100 Hz.

dave

[jrebman]

Isn't this the driver that's in the Cain-Cain/Lovecraft Noogie?

-- Jim

[floobydust]

 Yup, the FF85K is used in the Noogie... really cute little driver with the up/down suspension. I have a pair for some 2-liter boxes for my Son when he gets his butt up here to play woodworker.

 Regards, KM

[Poindexter]

Is the aluminum cap on the FF85 attached to the cone, Dave, or the pole piece?

Poinz

[DaveC113]

I'd suspect the pole piece rather than the Dave     

[jrebman]

Somebody told me that Dave goes around with lots of aluminum dust caps attached to him.

-- Jim

[chrisby]

Actually, the dust cap on FF85K (and FF125K) are attached to the cone, and EnABLing the aluminum and paper on this driver is quite a PITA.  If you can live with its limitations, the results with the 85K can be more than a little surprising - far more so than the 125K. I'd daresay that within its safety zone, this little guy could give some very exotic high priced tweeters a surprise, particularly when run on a small OB.   

Hopefully, Dave can recover from gift-mas and post some pictures of the latest creation soon - it's a teeny little box.

[planet10]

The FF85K is the odd man out in the Kenaf cone drivers... the design seems at least a half a generation ahead of the rest of the FFs. They have the trick Fostex surround and -- from the impedance curve -- a copper-clad pole-piece, The centre dome has a much higher degree of curvature and is much like a hemispherical radiator (more so than your typical dome). Fostex claim 32kHz extension for this thing, and it is believable.

All EnABLed up (along with our other tricks) this thing is really outstanding within its range. It is excursion limited to about 90 dB around the 100 Hz F3, but even in my largish room it doesn't do too bad. As a computer monitor (its design goal) the µFonken is a stunning speaker. It does need more power than the larger Fonkens and works really well with the KingRex we are trialling.

As Chris alludes this could well give some big buck tweeters a run for their money. Be interesting to hear them against some of the big ScanSpeaks. On the downside these run only about 87 dB

Here is a snap of the µFonken followed by a family shot that will give a better sense of scale.





dave

[Scottmoose]

I'm drooling here over those three boxes.

[jrebman]

Yup, those uFonkens sound really interesting for their size and intended use.  Hope I get to hear a pair one day.

-- Jim

[Ryerse Rocks]

I'm the guy who started this thread and watched it go off course somewhat. I'm finished the project, and for its intended purpose (casual background listening in a small room) it's pretty good. There is some colouratioin compared to my beloved Quad ESL's, and it lacks deep base for sure. I was considering buying a decent radio, but thought this would sound better - and it does by a long shot. I have it hooked up to some ILP kit electronics and a portable CD player right now. I will try it with my main system some day just for fun. The parts were well under a hundred bucks. I lined the sides with a mixture of drywall mud and glue and added a little stuffing in the back. I used 1''X8" pine for construction. Yeah, I know I should have used plywood or MDF. Remember though, this is for casual listening. When I have time I may try to break up any standing waves in the cabinet. For now I am happy with the results.

[planet10]

pictures?

dave