Original enclosures for Fostex 103's

[airframe]

I searched full range drivers and haven't found much mention about the enclosure suggestions from Fostex, is there a reason ? Will they sound pretty good? Has ANYbody built these ?? Am I just wasting my time??

My first build, I have a NAD 3020e amp that will power these, just want a small bookshelf units that will compliment this amp. Room size is about 10 x 16. I've selected 103's because they can be used in so many different enclosure types but for now I'll do these. Already have the 3/4" MDF and will use 1/2" apple wood front.

http://www.fostexinternational.com/d.../103e_encl.pdf

[planet10]

We built the Fostex horn, it sucked. Probably the best existing box for the FE103 that satisfies your criteria is Tony G's Solo 103.

http://www.humblehomemadehifi.com/Solo103.html



This thou is for the older FE103. I just got a pair of FE103e and will be working thru to something in the Fonken family for them.

dave

[airframe]

Ooops sorry should have said what enclosure on that page , looking at bass reflex unit at the bottom. And yes the new versions of 103's at Solen.

[chrisb]

I've had enough experience building more than one of the Fostex factory recommended enclosures for various drivers to offer the opinion that you could do much better than this particular BLH design for the FE103E .




To name a few:

Buschorn MKI (originally designed by Dr Busch for a 3" driver, but easily modified to fit the FE103E or even FE126 - I've built this for both the FE108ESigma and FE126 );


http://homepage.mac.com/tlinespeaker...chhorn-Mk2.gif

Tony Gee's Solo 103;

http://www.humblehomemadehifi.com/Solo103.html

Scott Lindgren's Vampyr;

http://homepage.mac.com/tlinespeaker...1v1-010109.pdf

GM's MLTL;

http://www.diyaudio.com/forums/showt...015#post535015

and for bipole;

http://homepage.mac.com/tlinespeaker...es-drawing.gif

This last design was my first serious entry in the crazy world of Single Driver designs, and I've built probably a dozen pair with vintage Foster alnico precursors to the FE103, as well as NOS and used RS 40-1197. Still somewhat limited at the extremes of SPL and bass extension, but in the right system can deliver a helluva soundstage, and definitely benefits from a powered woofer, XO'd between 100-120 IIRC


p.s.:

It looks like Dave beat me tuit, but for someone looking for a range of designs, particularly one not requiring stands, the list above still stands

edit: After reading your reply above, the question remains as to whether you're specifically looking at the little BR for simplicity of construction, or space requirements. By the time you consider the footprint and expense required for many little monitor designs (the Fonken stand-mounters included), a floorstanding enclosure can start to make sense - and they often deliver more extended LF response.

[airframe]

A little of both Chrisb, I guess, has the BR given by Fostex been built? So far I got $6 of MDF, I'll spend maybe $120 to get the Fostex here, some binder posts and the Apple wood on the front and of course my time. At the end maybe $140 Cdn. The questions still remains on the viability of the BR's. No doubt there are better enclosures out there but for size, lack of complexity, cost is the difference going to be apparent to the average listener like me? Are you going to notice it with Gordon Lightfoot, Simon & Garfunkel or Jimmy Buffet ?? We can all search for the holly grail of speaker enclosures ( so far I think that will be the BIB that I will eventually build) but for now has anyone come up with any real issues on the BR's, lets face it the average speaker out there is a BR enclosure of some sort !!

[Cal Weldon]

Originally posted by airframe
is the difference going to be apparent to the average listener like me?

Yes.

[i]Are you going to notice it with Gordon Lightfoot, Simon & Garfunkel or Jimmy Buffet ?? [/B]

3 of my favourites, with Jimmy (two t's) Buffett at the top of the pack. I run my Foster 10F3's in a BVR cabinet with a helper woofer in a separate cabinet with a plate amp. Very nice combo.

[airframe]

Cal, way to big, WAF very much in the red !!

[HareBrained]

Hmmm, if you haven't bought the drivers yet, why are you set on the FE103?

There are some other options out there that you may want to consider. The Mark Audio CHR70 for one. Cost will be less and you'll be very happy with their performance (I am). They're available in CA from creativesound.ca.

[airframe]

Hmmm gona have to look at those ??? Thanks, didn't think the cost was less actually! Anyone else try these in a simple BR yet

[chrisb]

Mark, FWIW, I've built a variation (i.e. revised aspect ratio of dimensions and additional bracing) of the Fostex recommended enclosure for the FE167. Compared to 2 other designs by Dave & Scott, (Fonken 167 and Demitri) it severely limited the driver's performance. I'm too lazy to experiment if that would be the case for every driver I might find interesting.

Our only enclosure built to date for the new Mark Audio drivers was a 6 litre sealed box for driver break-in for the CHR70 , and Henkjan's MLTL for the Alpair5. It's my intuition that the full potential of these drivers is not yet realized with these simple boxes.

Next up is the Lotus^2 for CHR70, but as circumstances limit my construction time, previously committed projects will delay completion of that one for at least a couple more weeks.

A final observation, based on several of my own earlier experiments - considering the investment in drivers and your labour, I'd definitely recommend baltic birch plywood for any of the contemplated enclosure designs. I've used it exclusively for the past 3 years now, even including boxes for my car install buddy.