this is like crack


2004-07-10 2:18 am
I can not stop building s*** . I have some Fostex 166 and am planning on building the BLH horn on the Fostex web site. Then I looked around in my room and realized it is the size of a postage stamp (12X12).
From other posts it seems that the room may not be suited for a horn
Is it indeed to small ?


Nelson Pass

The one and only
Paid Member
2001-03-29 12:38 am
If you have a small room and little space, the FE166E works
quite well in a .75 cu ft sealed box, stuffed, and driven by a
high impedance source. If you don't want to bother loading
down a current source to get the optimum impedance for the
bottom end response, then you can place resistance in series
with a conventional voltage source amp, say 5 to 15 ohms.
Using this arrangement also makes it easy to implement a
passive baffle-step correction. See the article on


Your comment helped clarify an idea in my beginner's head that it is far better to buy quality drivers than to fixate on a specific enclosure. It seems that the 166 can work in just about any enclosure, big or small, with proper tweaking and adjustment for room size.

This is very encouraging. I can't wait to finish my Buschhorn project and then start something else. But I think it's clear to me now to put my money into the drivers without worrying too much about the enclosure.



2004-07-10 2:18 am

I am using the 15 litre OEM encloser now with the FE167. I used
some fill and a little duct seal to tame it a bit.
I built the JE labs 2a3 for the amp , I like the sound , but the quest for audio nirvana has Conquered my sensabilitys. I thought the FE166 was designed for a BLH . Maybe I am just hyped about the woodworking challenge in building a horn. Provided a build a 21 litre sealed box using FE166 , is there much difference compared to FE167 in a 15 litre BR ?
golden ratio

qwad said:
:eek: yeah not just too small but the wrong shape, should be longer too , something close to the golden ratio also taking into account ceiling height too:angel: cheers and best regards, T.C.

Hi Qwad,

I might just encounter the same problem as our friend and his too small room. I gathered quite a lock of stock, amps, speakers and so on.. and I plan to build a humble workshop so that I can build and try amps, horns and the likes..

So, "before" starting building something, might be a good idea to as you what would be something decent for a small horn system. Ideally a two way that could be something like a 15" in a b-reflex, or a kind of Klipsch horn like speaker... and in the mean time, smaller blhorns like the Swan 101 and the likes.

Oh, and about the Golden ratio? can someone remind me what it is, and give examples of what a suitable room could be?
Re: golden ratio

Sylver300B said:
Oh, and about the Golden ratio? can someone remind me what it is, and give examples of what a suitable room could be?

phi = 1.6180...

the ratio 1:phi is the golden ratio

in a rectangular shape 0.618:1:1.618

The best rooms are not rectangular, but within practical limitations a significant number of the problems can be eliminated by having a roof that slopes in 2 axes (a normal vaulted ceiling would only be considered 1 direction -- but one with a "sloping" floor in the same direction as the peak (and then rotated so the floor was level) would be a practical realization of 2 axes slope).

my room has a ceiling that slopes in 1 direction and goes from 7' to 17' -- it is a really good sounding room. It has a few other features that help too.

SY said:

Is the slope in the direction of the centerpoint between the speakers to the listener? Or is it left-right wrt the speakers?

Right now the speakers are at the short end about a metre out from the wall, SAF dictated (and for practical reasons now that we have a TV). I prefer the room sonically oriented the other way where the closest the speakers can get to the wall is about a metre & a half. This end also has a large opening at the top into another room with the ceiling sloping in the opposite direction. (this orientation would also allow me to place huge subs on the ceiling of my workshop firing out into the main room)

About sloping:

Does it "count" as sloping if one builds levels? I can imagine constructing a slightly sloping ceiling, from taller to shorter wrt the listener/viewer, but I can't imagine a living space with a slightly sloping floor.

I can, however, imagine having three steps from back to front, say, over the course of 22 feet, to create a virtual slope, I guess.

kneadle said:
but I can't imagine a living space with a slightly sloping floor.

LOL... it was a descriptive mechanism... if you go back, you'll see that i said that you had to rotate the house until the floor was level....

attached is a quick isometric...



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