Fostex FE103E...

[planet10]

Originally posted by chrisb
you can get away with a box that's not a lot larger than the carton in which the drivers are shipped - i.e. 3/4 ft ^3 ( 21.26 liters)

At least by the sim, you could get away with a box as small as 1/8 ft^3 (3.5 liter). You have to be careful to get the driver to fit.... doubling the box to 1/4 ft^3 (net) gives you butterworth Q, doubling again to 1/2 ft^3 (14 litre) gets you Bessel.

dave

[Brisso57]

They're designed to be used reasonably close to a rear wall & with separate bass modules. A 4in FR driver with very little excursion does some things very well, but LF is not one of them.

Originally posted by chrisb


Well, let's call them stereo woofers not "subs" - as you'd likely be crossing them over much higher than 100Hz to achieve the maximum benefit with a FR driver as limited in low end power as the FE103E. Full 2-way XO circa 200Hz or so (rather than just lo-pass fill) makes sense to me - both to significantly reduce the bump in the modeled response curve, and to substantially increase total SPL limits.

Due to the very small footprint of the Vampyr (or Zigmahornet for that matter), I'd be inclined towards the smallest woofer enclosure possible. As it turns out, the CSS SDX7 is a stellar performer in a teeny sealed box ( thanks to Dave for the correction on my estimated enclosure volume posted elsewhere).

Particularly with an outboard amp to drive the woofers, you can get away with a box that's not a lot larger than the carton in which the drivers are shipped - i.e. 3/4 ft ^3 ( 21.26 liters)

A bit OT, but I have the perfect name for "stereo woofers" to assist Vampyr ... "Elvira" (or the plural). The namesake certainly helped to make the schlock-horror movies more interesting. :-)

[chops]

Originally posted by Brisso57




A bit OT, but I have the perfect name for "stereo woofers" to assist Vampyr ... "Elvira" (or the plural). The namesake certainly helped to make the schlock-horror movies more interesting. :-)

Actually, Van Helsing would be a much better name if you ask me.

[chops]

Just curious...

Could another FE103E be mounted to the rear of the Vampyr be used as a bipole setup? And if so, would there be any advantages to this other than great power handling and output, and of course all of the other traits of bipole designs?

[planet10]

Originally posted by chops
Could another FE103E be mounted to the rear of the Vampyr be used as a bipole setup? And if so, would there be any advantages to this other than great power handling and output, and of course all of the other traits of bipole designs?

Something like this?

http://www.t-linespeakers.org/FALL/bd-pipes.html



dave

[Scottmoose]

Originally posted by chops
Could another FE103E be mounted to the rear of the Vampyr be used as a bipole setup? And if so, would there be any advantages to this other than great power handling and output, and of course all of the other traits of bipole designs?

No, it'd need a dedicated bipole design (as the BD pipes Dave shows above are).

'Great' power handling is relative of course... FE103Es are lovely drivers in many ways, but along with LF, high SPLs are not part of the equation, and due to their polar response, acoustic power at the listening position isn't substantially higher, other than correcting for step-loss if an uncorrected speaker is being used away from room boundaries.

[chops]

Thanks guys.

I'm just running some ideas through my head because I'm thinking about just putting these 103's in my vehicle like I had originally planned (that was the whole reason for buying them in the first place), and upgrading to a bigger, better FR driver for home use. This is mainly due to the fact that I can't find anything decent or better than the 103's that I want to put in my vehicle without spending about $400, and I don't want to do that for dash speakers.

If you guys wanted to upgrade from the FE103E driver, what would be your logical choice, 4.5", 6", 8"? Also, should I go with another Fostex or should I also consider CCS and or Audio Nirvana? Those AN drivers really interest me.

One thing I want to do is stay completely with a single driver. I do not want to resort to using a helper tweeter. I also want them to be efficient.

Any thoughts.

Again, many thanks in advance!

[chrisb]

The BD bipole pipe in Dave's above post was originally designed by Bert Doppenburg specifically for a rebadged version of the FE103 driver.

They work surprisingly well, huge soundstage and very good mid-bass - but as with any FR driver this size, separate woofer(s) would be required for ultimate low end extension.

Several years ago we built more than a few pairs, with variants of the drivers from vintage Foster Alnico drivers (as shown in the photos), to RS 40-1197. We never did acquire any of the current production FE103E.


As for the upgrade question, that re-opens a whole series of questions relating to application / previous experience with FR systems / expectations / listening habits / room size / amplifier type and power, etc - there is simply no one-size fits all answer.

Having said that, IMHO the FE127E represents the best balance of overall performance and ease of application* of the affordable range of Fostex full range drivers. No doubt others have their own personal favorites, so don't expect any type of consensus.


* between designs for the FE127E by Dave, Scott, GM et al, many of which have been posted here, and which are also hosted on the Planet-10 or Frugal-Horn/Spawn site, there is probably a design that would work for you ( my own personal favorites for as much for aesthetic reasons as sonics). I'll repeat my now well known opinion - "it's harder to get the FE127E to sound bad than to get other members of the same family to excel"


next up would be the FE167E.

[chops]

Honestly, I've been eye-balling the FE127E very closely. However, I have also been eye-balling the CSS FR125SR. It has an incredible amount of Xmax but it is also a lot less efficient.

Then again, like you said, I could always go with the FE167E.

With any of these, I'm pretty sure I would go with some SDX7's on either side to help the low end.

What to do, what to do...

[chrisb]

Charles - provided you have the required power, the FR125 is a great driver, but if you like the midrange / top end of the FE103E, the FE127E would probably be the way to go.


Around the time we were playing with the FR125 & WR125 bipoles, we also played with a bipole MLTL with the FE127E -it might be nice to revisit that again, but it would likely be along the lines of bi-curious Fonken.