Fostex FE206en EnABL process and other mods

[CollinA]

Hello-

I've been surfing diyAudio for a couple years now, and I would like to ask some specific questions about EnAbling a pair of FE206ens. I have treated a pair of the older FE206s, but the the whizzers are all bent out shape by now, and I feel that I could do a better job, since they were the third pair of drivers that I have treated.

I've searched all over diyAudio, and still had some questions left over, so here goes:

1) There is a 10db hump around 10kHz on the older treated drivers. Any way to reduce this besides a filter?

2) Regarding the actual EnABL pattern, is it worth my time to add a middle ring, on the main cone beneath the whizzer? Where?

3) How about on the back of the main cone?

4) The 206s are currently in a pair of Sachikos (which sound wonderful, btw). How much improvement would I see if I EnABL the accessible areas (baffle, mouth, throat, etc.)? Would EnABLing all the internal surfaces/corners offer significant improvement over the currently accessible areas?

5) I was reading about Planet10 using SR-500 for basket stiffening. Since it's expensive stuff, and takes forever to apply, would a layer of powdered limestone/epoxy mix followed by a layer of ductseal offer similar results? Would the SR-500 be better?

6) Mamboni process:
a. How? What shape/size of felt?
b. Is it worth it?

Thank you! I look forward to hearing your responses.

[StoneT]

Bump
Having just bough a pair of these I'd be very interested in comments too.

[planet10]

There are some pictures of 206/207eN on my kermit thread including recent EnABL2

Pretty much the same story for FE206/207 as FE167 here (althou we are now into EnABL 2)

dave

[hm]

Hello,
did you made measurements to control what you have done, did you test other enclosures because the driver need support below 800 Hz that you can´t get by
a basshorn?

[StoneT]

The main issue I would like to address with these drivers (having still not listened to them yet) is the peak at 2.5KHz but i have not seen any info on whether it is addressed by EnABL or phase plugs or just reduces after break-in.
Without it, these drivers would seem to be very nice. I just need to build some cabs and get them out of that delivery box

[jgwtriode]

If you haven't found this mod yet...try this. It's a pain in the butt and you have to be careful not to bend the whizzer's but it can be done. Get some really thin foam about 1/8 inch thickness or close to that. Have to probably buy a sheet or find a foam company with scraps. Cut it long enoug to make a circle with the exterior diameter of the whizzer at it's base. About 3/8" to 1//2" wide.(YMMV) Edge glue it together. I used hot melt glue since it sets up fast. Now carefully stretch it over the flare at the end of the wizzer
and move it to the base of the whizzer. It will damp the whizzer to a mild degree. U can adjust the thickness to suit and see what you think. Initially err on the side of to long and too narrow as your practicing placement.

[chrisb]

Originally Posted by jgwtriode

If you haven't found this mod yet...try this. It's a pain in the butt and you have to be careful not to bend the whizzer's but it can be done. Get some really thin foam about 1/8 inch thickness or close to that. Have to probably buy a sheet or find a foam company with scraps. Cut it long enoug to make a circle with the exterior diameter of the whizzer at it's base. About 3/8" to 1//2" wide.(YMMV) Edge glue it together. I used hot melt glue since it sets up fast. Now carefully stretch it over the flare at the end of the wizzer
and move it to the base of the whizzer. It will damp the whizzer to a mild degree. U can adjust the thickness to suit and see what you think. Initially err on the side of to long and too narrow as your practicing placement.

even simpler, stretch out some cotton batten or fibrous "pillow fill" and loosely stuffed between whizzer and main cone - shouldn't take more than 5 minutes, and friction fit will be more than enough for a taste test

Eminence Beta 12LTA: