Fostex Driver question

[Shae]

Please forgive my noobness,

What are the differences between the Fostex FE167E & the FE168EZ? Are the differences audible?

Would it be worthwhile using the FE168EZ instead of the 167 in the Martin J King designed ML TQWT I'm planning on building? Any advice would be appreciated!

[planet10]

Originally posted by Shae
What are the differences between the Fostex FE167E & the FE168EZ? Are the differences audible?

Would it be worthwhile using the FE168EZ instead of the 167 in the Martin J King designed ML TQWT I'm planning on building? Any advice would be appreciated!

FE166 has a whizzer, and stamped steel basket. FE168eS (168eZ is a mis-tansliteration) has no whizzer, a cast basket, Fostexes (gorgeous) in.out surround *and spider), and quite a bit more complex cone.

The FE168 should sound better (i've unfortubatly not heard it), but it may not kust drop into the ML-TQWT. i'm not familiar with a MJK ML-TQWT for the 166. He did one for the FE164 and the FE167 is a drop0-in replacement for it.

dave

[Scottmoose]

Aha. One of my all-time favourite boxes. The FE167E is a drop-in replacement for the defunct FE164. The FE168ESigma unfortunately will not work at all well in that cabinet, so if you're wanting to build it, I'd stick with the 167 & add phase-plus, basket / magnet damping, EnABL etc.

[hm]

Hello,

a main difference is the Xmax,
168 is useful in a bass horn like my TUBA,
167 has only 0,6 mm only useful by taking two
like in my POSAUNE.

[Scottmoose]

...by your opinion. Fair enough. But plenty of people are also happy with it run solo. Witness the thousands of satisfied builders of cabinets with a single unit mounted. Fostex sell a shed-load of these units globally every year.

The 167 overloads very gradually, and distortion is not generally audible, except on demanding pieces at high SPLs. It works very nicely for nearfield listening in a small BR box, or MLTL like Bob's FT1600, on the music they are designed for -small to medium-scale classical ensembles, folk, blues, light rock etc. They don't make a bad fist at heavier stuff considering that's not what they're for, though personally I'd prefer larger drivers with dedicated woofers & supertweeters for that. 167s do many things well, but Pink Floyd in Pompii at ~live levels is not exactly their forte. Sally Oldfield is currently sounding rather nice though my own 167 MLTLs as I type this actually.

[hm]

Hallo,

my experience shows take the 167av only near TV,
the 166E has bit more highs IMO.

compair the graphs:
http://www.fostexspeaker.de/gehaeuse/168ez_encl.pdf
to much clay tone between 150-350 Hz, covers the bass,
and makes colouration.
http://www.fostexspeaker.de/fullrang...ma/fe168ez.pdf
on an IEC baffle !


therefore i prefer a bass horn working only below 150 Hz.

and I prefer horns because you didn´t use the resonanz
of the driver.

scoutmoose, you are right, different enclosures are possible.

[Scottmoose]

Is that a Jordan in the pictured box Horst?

Yeah, the 166 has slightly more HF than the 167, whch rolls off a little earlier. Suits me as I find a slightly rolled off treble easier to listen to for extended periods. It usually needs some correction to work in a box other than a horn though, so the 167 is a bit more versatile.

The Sigma's a lovely unit -I completely agree with you that that Fostex horn isn't one of their better efforts. Something like this 25 litre reflex box with massive end-correction on the vent (i.e. a short horn) I've quickly roughed up gives equal LF extension, a much smoother response and excursion's no more than 0.6mm (total) at 70Hz, 1w / 1m.

[Scottmoose]

Predicted driver excursion for the above box, 1w / 1m. I usually only post FR graphs to avoid clogging threads up, but as I know you're interested in the subject, I thought I'd add it. Not a finished design as I say, just something I quickly knocked together now. They don't support the cone as well as small chamber / chamberless BLH at high SPLs, but at reasonable levels these boxes do a very decent job, & don't suffer from the response problems many others have.