FF85WK uFonken vs. Bass Reflex

[RickH]

Hello All,

I am ready to order the goods for my first build. I want to make something small and simple using the Fostex FF85WK in either the Fostex-designed bass-reflex (3.5 liter) or the uFonken (2.2 liter?). Both enclosures do not look too difficult to make.

Could someone please let me know how different the two enclosure types would sound? Thank you,

Rick

[chrisb]

Originally Posted by RickH

Hello All,

I am ready to order the goods for my first build. I want to make something small and simple using the Fostex FF85WK in either the Fostex-designed bass-reflex (3.5 liter) or the uFonken (2.2 liter?). Both enclosures do not look too difficult to make.

Could someone please let me know how different the two enclosure types would sound? Thank you,

Rick

they're so small that you could likely build both from a single sheet or even offcuts, and report back to the class?

use good plywood, or if you're confident, solids like knot free pine, walnut, mahogany, etc not MDF


A few years back I built two pairs of small vented enclosures for FE127E - identical in volume and tuning frequency; one with standard round port, and the other with narrow slot vents (which in small enclosures are easily incorporated into bracing scheme)

The standard BR had more pronounced lump in the frequency response, while the slotted design was leaner in that area, but had more definition (I like to use the term articulation), and extended deeper and more smoothly. The latter design became the template for what Dave now refers to as the "milli & micro" series - with adjustments in CSA and depth of slot vent, including the use of filler/spacers, this topology easily allows for a wide range of adjustment for different driver's T/S parameters.

If you'd like more of a fabrication challenge, look at the trapezoids - the FF85Wk in these are quite a surprise for a lot of folks.

[planet10]

Originally Posted by RickH

the Fostex-designed bass-reflex (3.5 liter)

A simulation of the factory BR is not encouraging, but not the "cruel joke (jw)" that the FE126En factory BR is.

The uFonken is 2 litre, the uFonkenSET 2.5 litre

dave

[RickH]

Chris and Dave

Thanks for the replies. Fonkens also look a lot cooler than the Fostex
BR.

What driver is the uFonkenSET for and how do I get plans? Thank you,

Rick

[chrisb]

Originally Posted by RickH

Chris and Dave

Thanks for the replies. Fonkens also look a lot cooler than the Fostex
BR.

What driver is the uFonkenSET for and how do I get plans? Thank you,

Rick

FF85WK - email Dave

if you do proceed with the build - PM me for some fabrication suggestions - I've built more than a couple of pairs of virtually every Fonken design out there

(sorry, couldn't resist)

[planet10]

Here, BTW, are pics of Chris' personal uFonkenSET



dave

[RickH]

Chris' uFonkenSET look so good that if you didn't feel like listening to music you could just look at them. Now I have some ideas for those slabs of black walnut I stuck in the attic.

I figure I'll start with the standard uFonken (in plywood) then maybe try something more exotic (and bigger). I kind of like the FX120 - Is that a Fonken-Steen? Thanks,

Rick

[planet10]

FX120 goes into Fonken-steen. There is also a designed, but never built, floorstander that should be a bit more aesthetically pleasing.

dave

[planet10]

Originally Posted by RickH

Now I have some ideas for those slabs of black walnut I stuck in the attic.

That was a lucky guess on my part... i could have posted pics of locust, yew, cedar, or the lovely veneered ply, or the newest Douglas Fir (aka pine) ones.

dave

[chrisb]

Originally Posted by RickH

Chris' uFonkenSET look so good that if you didn't feel like listening to music you could just look at them. Now I have some ideas for those slabs of black walnut I stuck in the attic.

I figure I'll start with the standard uFonken (in plywood) then maybe try something more exotic (and bigger). I kind of like the FX120 - Is that a Fonken-Steen? Thanks,

Rick

while I'm the surprised recipient and happy host of the walnut beauties ( I'm enjoying the continuing offgassing of their rubbed oil finish as I type this), credit for their fabrication and all the solid wood boxes pictured throughout this forum goes to Bernie

Fonkensteen/(stein) was my nickname for the much larger enclosure for the F120A drivers originally commissioned several years ago for Jim Rebman. I did manage to hold them hostage for a while before shipping them off, and there's definitely something beguiling about the combination of an Alnico FR driver by engineers with the experience such as the Fostex crew and a dialed-in and lean DHT amp ( Bottlehead Paramour 2A3 in my case) - but I digress and reminisce too much.

IIRC the ceramic magnet FX120 can work in a smaller volume, but as much as we try neither Jeff, Bernie nor I have the time to build every variation that Dave can imaginate - which is a whole lotta enclosures