FF105wk above 3k

sean1975

Member
2016-05-28 6:20 am
I don't think that anybody will argue that these need a sub. But I don't hear many people saying that these drivers need a tweeter above say 3k....but conventional speaker wisdom/physics says that they do. Even 1.25 inch dome tweeters and some 1 inch tweeters struggle at the highest audible frequencies and can sound harsh. So I guess my question is, do these 4 inch drivers beat the law of physics and put out smooth highs at 15-20k or do they sound harsh and that is part of the compromise of full range? Thanks
 
Many full range drivers rely on some level of non pistonic cone behaviour for treble range and invariably create some resonsnce peaks that sound harsh to some people. The driver you reference has a nasty resonance at 7500Hz in measured data. I had a Fostex driver lke that once (FE127) and couldn't live with it. I tried a notch filter, I tried modge podge cone treatment but nothing was great so I gave up on that driver. Full range drivers have many compromises and it takes good design, good materials and good manufacturing to produce good sounding drivers. My advice is avoid reliance on cone treatments or notch filters.

I Have used the Alpair 10.3 and can recommend it. In the Pencil enclosure it performs well.
 
Last edited:
The clever metal dustcap extend the high frequent. This is not quite as smooth as the smaller FF85wk, but better than the FF125wk which has more issues, like Bigun's FE127.

The FF105wk is still quite good. F10 below 60 Hz in a mFonken105, probably similar in the Woden Baby Lab, and Vampr-V 10 Hz lower.

But the dustcap has some minor ringing and the surround attachment has some issues. You can see the pattern on the dustcap to suppress the ringing, and an extra ring at the surround as well as ZIG 2-way glue at the junction on the back.

FF105wKeN-front.jpg


As Gavin says Alpair 10.3 (and the paper cone version) are excellent. They do need a much larger box.

dave
 

ssportclay

Member
2010-01-16 12:16 pm
Yeah that 7k peak could be nasty in nearfield. It looks like the FF85wk is less peaky and might be ok without EQ. Would equalizer apo be useful to turn down the gain at 7k? thanks

My thought is that equalizers are evil and compromise quality. You are placing more junk in the signal path that actually keeps you from hearing the signal itself which is the whole point of high fidelity. The FF85wk is a very nice 3" driver. If you want more bass in an attempt to have it all in a full range driver, I would suggest you look at the 4" Alpair 7.3 metal. If this will not do it then will will probably have to go 2-way.
 
The A7.3 can be fit into the same milliSize box as the A6p, but the A6p excels in that size and the A7x sounds just a bit constrained.

The milliSize box is about 5 litre -- close to optimum for the A6p. For the larger driver i would not try to put it in a box 6" skinny (at least not made of conventional material) as you get sufficient side reflection back thru the cone as to considerably degrade the performance.

dave