Kudos for pointing this out. I didn't realize big cabinets could image until I learned this a few years ago.
All i had to do was think availability and they were gone. I do have a single that has a companion with a small dent in the dustcap. Buy 1 get both. I was holding them forNYOne, but he has not responded to any emails.
dave
This driver is $38 and has an efficiency of 87dB. It's very very very limited in xmax - just 0.35mm. It has a conventional motor and no shorting rings.
This driver is nine dollars more. It has 3dB more efficiency. Even better, it's a prosound unit conservatively rated to take more than twice the power of the Fostex, and nearly ten times as much excursion It has an underhung neodymium motor. Distortion is likely lower than the Fostex.
It's a heck of a driver - one of my favorites.
I was once very interested in this driver, until I came to the conclusion that there was simply no way that it really had a sensitivity of 91 dB. In fact, take a quick look at the parameters, and it's easy to see that the Fostex is likely to be slightly more efficient. So, in regards to the 3FE20, either they've defied physics and the numbers are way off because they want to keep it a secret, or they're lying -highly likely since they're marketing it as a "professional" driver, and sensitivity ranks very high in that market.
On the other hand, have you measured this driver's 1w/1m response on a flat baffle? I'd love to see it, seriously. I'm still curious about this driver. I started a thread on it some time ago asking about sensitivity, and no one posted. So far, I still only see one possibility here.. which is that sensitivity is more like 86 dB 1w/1m, if that.
We can calculate efficiency using the published specs, so it should be pretty easy to see how the two compare. The Faital's re is 6.2 versus 7.2 for the Fostex.
I'm a big fan of small drivers - I have a pile of them that I've tried - but xmax is a very very important parameter IMHO
For instance, Madisound and Parts Express have been selling some inexpensive Aurasound woofers, and the cheap ones sound 'congested' due to the limited xmax. The more expensive ones, with more xmax, are noticeably easier on the ears, because it's easy to run out of displacement when your cone area is so tiny.
I was talking along the lines of sensitivity, rather than efficiency.
I was also looking at the discontinued FF85K that I'm dealing with here, rather than the current FF85WK. In that case, Fs is lower and Mms is higher with the 3FE20. FF85K has extended HF, and a cool surround that doesn't protrude out from the cone. And if Dave's measurements are reliable, it has the flattest impedance curve of any conventional 3" driver I've ever seen. Regardless, it seems as though the 3FE20 is no more, replaced by other drivers (3FE22 and 3FE25). Looks like US Speaker might still have some though, but for $46 each, I'll pass. I wouldn't expect any more from it than your average TB 3 incher. IRT the xmax thing.. when you're using it as a large bandwidth tweeter with a series 1st order, excursion isn't of much concern. Even then, while certainly limited, the FF85K doesn't seem to have any problem moving a couple of mm.
I was also looking at the discontinued FF85K that I'm dealing with here, rather than the current FF85WK. In that case, Fs is lower and Mms is higher with the 3FE20. FF85K has extended HF, and a cool surround that doesn't protrude out from the cone. And if Dave's measurements are reliable, it has the flattest impedance curve of any conventional 3" driver I've ever seen. Regardless, it seems as though the 3FE20 is no more, replaced by other drivers (3FE22 and 3FE25). Looks like US Speaker might still have some though, but for $46 each, I'll pass. I wouldn't expect any more from it than your average TB 3 incher. IRT the xmax thing.. when you're using it as a large bandwidth tweeter with a series 1st order, excursion isn't of much concern. Even then, while certainly limited, the FF85K doesn't seem to have any problem moving a couple of mm.
Okay, I plugged the specs into hornresp. At 1khz, the Faital appears to have about 2.5db more output. Obviously at low frequency this gap narrows, because the Thiele Small parameters of the two drivers are so similar. So at low frequency, they're practically the same. (The hornresp plot is a vented horn with 1.2 liter of back volume and a 1" x 3" port.)
The real advantage of the Faital is it's xmax, which gives it more headroom at low frequency, and it's underhung motor, which should reduce it's distortion when compared to a ferrite motor.
As far as comparisons to TangBand, I think it's a moot point. TB drivers are oriented for hifi, and tend to have more low frequency output at the expense of efficiency. The Faital's efficiency is more in-line with the Fostex drivers, but higher.
Attachments
The old FF85 was a sigma in disguise. An accident with a nice little Hitachi receiver left meone to disect. I confirmed that they have a copper cap.
dave
Oval drivers are a bit of a fetish with me. Are there no good current production drivers outside of automotive applications?
Would the "oval" TBs have any advantages due to the shape?
When using oval drivers in an array are they mounted long-ways or short-ways so the centers are as close as possable.
BTW. Thanks for your time here answering posts with your business to run and being a caregiver. Very appreciated.
Would the "oval" TBs have any advantages due to the shape?
When using oval drivers in an array are they mounted long-ways or short-ways so the centers are as close as possable.
BTW. Thanks for your time here answering posts with your business to run and being a caregiver. Very appreciated.
elliptical drivers interest me alot (rather than the TB type ovals). Mostly the ellipticals Ive encountered have been pretty awful, (though I stopped looking for good ones over a decade ago), and im no expert in that particular field.
Ellipticals interest me since reading V. Capel's book when I was 13 or 14. It would seem to me that they have the advantage of (generally) a broadened/lessened in Magnitude lateral cone resonance. I forget the correct term...(im studying an electrical/control systems degree, and knowledge seems to escape my brain as quickly as I fill it....)
Should the likes of Mark Audio persue an elliptical 4" by 6" or 6" by 9", then I should most certainly be interested in seeing a little more, since I havent seen any ICE ellipticals that had a particularly good response(FR/co-axial or midwoofer type-perhaps I havent looked hard enough. Any that seem to be generally available in the UK, are either in TVs or turntable/amp combos from the 70s. These are in general pretty awful, though surely some good ones must exist, even if theyre as rare as rocking horse $***.
Saying all this may sound like im damning all ellipticals, but im not. Id love to find some to make a good 2 way or coax, or FAST if i could find a small enough one to compliment.
Ellipticals interest me since reading V. Capel's book when I was 13 or 14. It would seem to me that they have the advantage of (generally) a broadened/lessened in Magnitude lateral cone resonance. I forget the correct term...(im studying an electrical/control systems degree, and knowledge seems to escape my brain as quickly as I fill it....)
Should the likes of Mark Audio persue an elliptical 4" by 6" or 6" by 9", then I should most certainly be interested in seeing a little more, since I havent seen any ICE ellipticals that had a particularly good response(FR/co-axial or midwoofer type-perhaps I havent looked hard enough. Any that seem to be generally available in the UK, are either in TVs or turntable/amp combos from the 70s. These are in general pretty awful, though surely some good ones must exist, even if theyre as rare as rocking horse $***.
Saying all this may sound like im damning all ellipticals, but im not. Id love to find some to make a good 2 way or coax, or FAST if i could find a small enough one to compliment.
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Many years ago some-one in UK designed what he called a differental wave driver. From memory it was a modified Fane round unit, with an aluminium oval glued to the inside of the paper cone. Written up in HiFi News when it still published good stuff. Claimed it gave a much smoother frequency response with fewer resonances. I have the article somewhere. Anybody else remember that?
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