Snail horns for FE166en?

[StoneT]

Just about finished a design for my first speaker build but would like to run it past the peeps here for comments. I can't afford the time or money to build something which I then scrap because I can't stand the sound, so if anyone can point out improvements or forseable problems that'd be appreciated.
I've based the design around the FE166En mainly because of the extension at both ends. I'm looking for speaker that can handle ANY music I throw at them, from drum+bass to Vivaldi, Chilli Peppers to new age didj. I've spent ages tweaking in Hornresp and seem to have come up with a reasonable response but I'm unsure how accurate the program is for what I'm asking it to simulate, this is not a simple horn.
So:
Camber ~ 8l, I know this is big but I can fill with stuff if it proves too much in practice
Horn mouth - 80cm2 giving a compression ratio of 1.66 starting a series of horn segments looking much like a space rocket when straight Then curled up into a kind of snail shell arrangement.
I have attached the Hornresp parameters, SPL response and a cad image of the design in a 300mm deep cabinet. I'm not afraid of a little woodwork and have a fully equipped workshop at my disposal hence the less conventional enclosure. I am however limited on space for these by room geometry / WAF. If anyone has any ideas to extend the bass without increasing cab volume I'm all ears. I was originally aiming for about 10Hz more but don't seem to be able to achieve that without a cab that's under 200l, and I don't even know if it's realistic with this driver. The current design is around 150l. I know the schematic doesn't show the final segment but that will be formed by a bend forward into the room and corner / alcove placement.
Any comments greatly appreciated

[hm]

Hello,
this design has a very short way and a long, i dont think that you
can simulat this exactly, to dam the presschamber makes it larger,
for that size i would prefer my double horn POSAUNE much more bass
less membran movement better soundstage:

[StoneT]

Thanks Horst. I've seen that design many times, very interesting. I should imagine it sounds fantastic. However, unless I'm mistaken it uses 2 drivers per cabinet, which would near double the cost for me. Also they would not fit where I am allowed to put the by my better half, she would prefer something highly 'aesthetic'.
I'm afraid I dont understand 'to dam the presschamber makes it larger' but the horn length as shown is a little over 2m and has no very short way as you say.

[hm]

than you don´t understand,
the snail folding has one short way and one long,
what gives an aesthetic looking if it does not sound.

Dam material enlarge the volume, 8 L without dam material
will sound bad, do you simulate it?

For the Posaune you need only a very cheap back driver.

[Scottmoose]

Eh? As far as I can see, it's one horn, folded / turned into a spiral. Axial horn length is generally taken up the centre of the expansion (as roughly hand-draw in the attached), so I'm not sure where the one short, one long comes from. Am I missing a 2nd horn here?

[StoneT]

I thought it was one horn too. apparently hm knows my design better....
Horst -"dam material"? Do you mean stuffing? Why do you think the 8 l chamber will sound bad? Too much excursion? Anyway as I said- the volume can be reduced post construction fairly easily so I'd rather start too big than too small. The potential for using a cheaper back (bass) driver for your design is very interesting and could be used for many applications. What kind of driver would you suggest? It would presumably still need a suitable Q for horn loading? Also - how are they wired? series would seriously affect the performance of fostex while parrallel would reduce impedance. these speakers will be driven by a ~8W/channel Class A P/P tube amp requiring as high impedance and high efficiency as possible. Your Posaune is very nice and your design principles inspiring, but not for my application.

One thing I'm wondering is how low to go? Most BR designs seem to reach 50Hz but if I'm aiming not to use a sub is the response shown adiquate? I suspect not...

[hm]

look your pic, the left line is much shorter as the right.
simu your imp, IMHO not good for a tube.

look and read my double horns, much more bass as a single horn,
much better imp. For the Posaune you can take a lot of drivers,
SPH 165 Monacor, it is a bipol, drivers parallel.

But thats not the point, built yours and show us the measured result please.

"Why do you think the 8 l chamber will sound bad? "
experience

[Scottmoose]

What left & right line? There's only one horn, not two, & axial horn length is generally taken up the centreline.

[brsanko]

A larger rear chamber puts less preasure on the back of the driver and therefor gives less damping and flabby uncontrolled bass, adding stuffing will make this worse not better. Check the impulse response in hornresp.

[hm]

scotti,
the line left and right of the axial line. thats because it is a snail,
do you get it now?