FF225K+FT17H in BIB

[testarossa2k]

Hi, I finished building the BIB enclosure for Fostex FE206E. I like everything beside the high, after sometime they cause listening fatigue. Because I must put the BIB in the angle, the sound became harsh,but I must say that the room isn't furnished a lot and it has some echo.

The Fe206e are of my friend, and now I must buy one pair. But I was thinking to buy the ff225k+FT17H. The ff225k seems more smooth in FR graph, isn't it?

thak you

[OzMikeH]

Are the borrowed FE206E fitted with Phase plugs?
These drivers are not good at the high end without the duct cap cut out and phase plugs fitted.
I have the very similar 207 and phase plugs made a massive improvement to the high end.

I have no experience with the 225k. Surely one driver might be better to try with improvements? then add a tweeter later if you are still not happy.

[Scottmoose]

Phase plugs make a dramatic difference to the highs of the 206. The 225K with FT17 also works well in a BIB box though -I built a rough pair using just these units for a friend 20 months back, and he's a happy camper. Even his wife liked them, once he'd neatened the boxes up (I can't build attractive cabinets).

[testarossa2k]

anyone got FR with and without phase plug?

[OzMikeH]

I used to have some without... then I took a scalpel to them. Does that count?

The difference between with and without on the FE207 is very big, It's like a driver that costs twice as much.
the difference is only in the highest frequencies. it does not alter the midrange and bass at all.

[testarossa2k]

and if I use this
http://www.tymphany.com/datasheet/pdf/pl/830869.pdf

and this
http://www.fostexinternational.com/d...pdf/ft207d.pdf

with a 6 or 12db crossover.

Someone please could make a simulation with that woofer?

[OzMikeH]

I'd be tempted to use the dramatic rolloff of the Tymphany at 4kHz with some gentle additional filtering, perhaps a 6dB filter on that with a 12dB on the tweeter. Phase response would be all over the place. That may not bother you much, also crossing over that low means any deficiencies in the crossover are more easily heard. That slight rise right at 3k is also worth bearing in mind when designing your crossover.

With the odd shapes you can get those drivers extremely close together, you could even trim 2 of the wings on the tweeter. A very big advantage.

Bi-amping these with a steep active line level crossover at just over 3k would make a very nice speaker.

[Godzilla]

>>> But I was thinking to buy the ff225k+FT17H.

Based on what i heard with the ff165k + RS pod super tweeter, i would imagine the 225k + FT17H would be nearly as good as it gets in the world of speakers. I wouldnt hesitate to buy this combination and build BIBs for them if i had the room to handle the size of the cabinets.

http://www.zillaspeak.com/bib-godzillabib.asp

Godzilla

[Scottmoose]

They do work rather nicely.

[testarossa2k]

If I buy the ff225k+ft17h I will put them in the same cabinet of the Fe206E. I don't want to rebuild nothing. I think it should work, the fe206e and ff225k seems close on T/S parameters.