12.5 foot folded horn in a smallish box?

Douglas R. Allen

Douglas R. Allen

Sophomore
Jan 11, 2011
297
15
18
Maine USA
Looking around I noticed these.

XS-21 Chimera 18" Bass Horn - Ramsdell Pro Audio

They state a 12.5 foot folded horn in a 30" deep, 22.5" wide, 30" size box. Although the woofer magnet is in the horn mouth this still doesn't leave alot of room for the horn size stated. Would each fold only be an inch or 2 high? That would have to be somewhere around 5 or so folds if I have it figured right.
Does Danley have that long of a horn folded up inside their boxes? Is this a Danley Clone or something else?

They even have a 21 inch woofer in a 36 deep, 36 wide, 25.5 tall (inches) box with a claimed 14.5 foot long folded horn. A rated 140 db output.

XS-21 Chimera 21" Bass Horn - Ramsdell Pro Audio Products

Anyone have a diagram as to how they get that long of a horn in such a small"ish" box?

If they were something like these I guess I could see it.

http://www.freespeakerplans.com/bass-cabinets/11-cubo-18

I was unsure as to where to post this so please move as needed.
Thanks;
Douglas R. Allen
 
Re: 12.5 foot folded horn in a smallish box?

Douglas R. Allen said:
Looking around I noticed these.

XS-21 Chimera 18" Bass Horn - Ramsdell Pro Audio

They state a 12.5 foot folded horn in a 30" deep, 22.5" wide, 30" size box. Although the woofer magnet is in the horn mouth this still doesn't leave alot of room for the horn size stated. Would each fold only be an inch or 2 high? That would have to be somewhere around 5 or so folds if I have it figured right.
Does Danley have that long of a horn folded up inside their boxes? Is this a Danley Clone or something else?

They even have a 21 inch woofer in a 36 deep, 36 wide, 25.5 tall (inches) box with a claimed 14.5 foot long folded horn. A rated 140 db output.

XS-21 Chimera 21" Bass Horn - Ramsdell Pro Audio Products

Anyone have a diagram as to how they get that long of a horn in such a small"ish" box?

Thanks;
Douglas R. Allen
Click to expand...
Most tapped horns have a path length of about 1/4 the length of the LF corner frequency, 12.5 feet looks a bit long for the XS-21 Chimera 18" Bass Horn considering the F3 of 36 Hz.

As far as being a "clone", it is a different shape than any present Danley TH, so is not a copy. Patents for cabinets with fold patterns with the speaker out similar to what Tom's TH look like have been granted as far back as the 1950's.

The fold pattern below of DIY er Xoc1 is similar to the DSL TH-18 (and is the exact exterior size), about 9.75' path length.
By making the first folds thinner getting a 12.5' path length would be possible, though the sensitivity would take a big hit as the F3 would drop to around 23 Hz with that long of a path.

Art
 

Attachments

  • Xoc1 TH18.png
    Xoc1 TH18.png
    381.8 KB · Views: 5
Re: 12.5 foot folded horn in a smallish box?

Art Welter said:
Most tapped horns have a path length of about 1/4 the length of the LF corner frequency, 12.5 feet looks a bit long for the XS-21 Chimera 18" Bass Horn considering the F3 of 36 Hz.

As far as being a "clone", it is a different shape than any present Danley TH, so is not a copy. Patents for cabinets with fold patterns with the speaker out similar to what Tom's TH look like have been granted as far back as the 1950's.

The fold pattern below of DIY er Xoc1 is similar to the DSL TH-18 (and is the exact exterior size), about 9.75' path length.
By making the first folds thinner getting a 12.5' path length would be possible, though the sensitivity would take a big hit as the F3 would drop to around 23 Hz with that long of a path.

Art
Click to expand...

Y'all knew I'd have to show up here and add my 2 cents worth didn't ya?!

I'm probably the only person on this board that has had a chance to actually hear these things. The Ramsdell shop is very close and I stop by to see how things are going often. I've been watching these Chimera cabs as they were being developed and no they are not like that drawing that Art provided. They are something altogether different. I've heard them around the shop in various configurations - the prototype 2x10 that was scrapped for the single 12 that inspired the 15 - 18 and 21. I've heard the 21 version side by side with another beast of a sub called the Sub Engine. Ramsdell Pro Audio - Products - Sub Woofers - The Sub Engine Both have formidable output and go very low but the Chimera in my opinion would be best suited as a sub-sub and used in multiples no higher than 70hz. That sub engine is a hard cab to beat for the size - weight and output down low ratio but if you have music that needs to get lower than mid to low 30's then multiples of these Chimera's will get you down into the 20's.

In short - the Sub Engine seems to pound a little harder in the typical bass and kick drum area of subville but the Chimera will dig a little deeper towards China - they're both great sounding subs.
 
Re: 12.5 foot folded horn in a smallish box?

Thanks for the replies.

Gene;
Could the folds be "something" like these in the enclosed photo?
Douglas R. Allen
 

Attachments

  • Long Horn.jpg
    Long Horn.jpg
    56.8 KB · Views: 3
Re: 12.5 foot folded horn in a smallish box?

Douglas R. Allen said:
Thanks for the replies.

Gene;
Could the folds be "something" like these in the enclosed photo?
Douglas R. Allen
Click to expand...

Maybe a little like that - but it has some kind of strange thing going on with the back pressure and the way it's mounted. It seems that all the gifted speaker cab designers have a special secret sauce they put on their cabs that the others don't have. There are countless posts on these forums attesting to the design mojo of Danley and even the Growler sub fellow but it seems I'm the only one here that has bothered to testify on behalf of Ramsdell. Most cabs are just boxes that have bracing and appropriate port and air space but some cabs like the Sub Engine and Chimera have some serious design effort involved.
 
Re: 12.5 foot folded horn in a smallish box?

Eric Cagle said:
That looks like Josh Ricci’s Gjallerhorn. I have been wanting to have a pair of those built by a good cabinet maker.
Click to expand...

Yes that is where I picked up the picture. It sure is a monster! If you get a chance be sure to post your listening results.

Douglas R. Allen
 
Top Bottom