21 inch long throw horn

Cone Material: No pressed pulp carbon fiber reinforced
Max. linear excursion (mathematical): 15 mm
BL Factor: 39 T · m

So what's wrong with LF21N551? Do you only want PD?
I just tried lf18x451 in a superscoop, it's crazy i tell you!


Edited by tv00 - 04 January 2015 at 12:03am

i have a symmetrical 21" horn design with magnet in horn available, 140x 70 x 90 cm, 35 hz horncutoff.
PN me if you have a serious interest in building them...

Nice will u post it?
The rcf is not as heavy, I used to have 2 pcs pd.2150 too, but they're gone now.
It's good to try new brands in new situations, for instance I found that the new fane 15xs & 12xb sims very well in tapped horns. Apart from cyclops I didn't see much of that.
I'm going to try that soon.

Hi, Please post plans and I will make one and try it out. Thanx, VECTORDJ

I just remembered when I started messing around with this idea, the original thought was to take WSX style folding and scale it up with roughly 1220x1220mm side panel surface to make most use of full sheet. I wanted to use letterbox styled throat as in certain way I see it as the purest form of horn loaded bass enclosures. Because 21" driver and somewhat large size, I thought it should go as low as reasonably possible. After fooling around with WSX style folding I decided to approximate other folding schemes. In my eyes, "S folding" will give longer horn as WSX-styled folding and also it has added benefit of having slightly straighter horn path with the first fold being not quite as steep. "C fold" is quite clean and nice design, but for given box size it will almost always give slightly shorter horn than "S fold" will.

So in the end the thing ended up looking like 1850/186 horn on steroids with Martin Audio inspired throat.

I quite hope someone would have time to see if it is worth something.

Even with horn mouth this big I'd estimate that having six of these in single stack would give mouth area big enough to support wavelengths getting closer to 30Hz. I always tend to say that as a rule of thumb with horn subs, you need four two man liftable boxes to have big enough mouth to do the job properly. With horn lengths between 1.6 to 2.2 meters or so, it tends to be like that. With proper 30-35hz horns I think number is preferably six, although with four the results are usually more than satisfactory.


Edited by pfly - 11 June 2015 at 8:44am

Let me know if you build one Francis!
I have a 21sw1600ND and a friend has two 2150s if you want to test:-)
Look at the rcf lf21n551, impressive specs & nice price at teamaudio and around, 18sound is brutal, but more expensive.