JBL 2418h

[bassnkeys]

I have a pair of 2418h drivers and bi-radial horns I'd like to use in a two way design. I don't need to get high sound pressure levels from them... home not pro use. How low can I go with a crossover point? Opinions? Experiences?
Thanks,
bassnkeys in MN

[norman bates]

how big is the horn ? Which horns do you have ? 2344 ?

jbl crosses it over (3622n) to a big horn (15" x 30") at 1,300hz. That same horn also can be crossed at 650hz.

I'm not sure where the driver naturally rolls of (plane wave response). No matter what horn, I'm thinking to cross 24db @ or above 1khz.

Norman

[bassnkeys]

The horn lenses are roughly 6" x 12". They are from stage monitors. I think I'll need a mid or a different horn/lens combo. It seems as though JBL only used them above 1200 at the lowest, usually above 1500. My low drivers are 2235h's.

[norman bates]

er, that's a small horn, I'm thinking 1,500hz seems right, but loaded on a baffle, it may go a bit lower.

But crossing that high is awfully high for a 15", but your ears may disagree.
I think the 2235 rises in response past 500hz, rolls at 900hz, has a couple of resonances at maybe 1,300 and 1,700. And you will lose off axis response past 800hz.

I'd recommend a larger horn and/or a smaller woofer (like a 12") or 2 to catch the compression driver.

Norman

[bassnkeys]

I'm thinking of going with a larger horn. A three way would be another route in which case I'd have to go to electronic crossover as I'm not engineer enough to do a 3 way X-over design for horns. Any ideas on a large horn/lens to match up with my 2235's? X-over around 800hz maybe.
Thanks.

[norman bates]

hmm........

I use a 750hz crossover point, but my horn is 14" x 24" and I use a 1.4" compression driver. A good compromise for a large 2-way for me. I can run it that low (with a large enough horn) because the the compression driver goes fairly flat low on a plane wave graph versus most 1". And it goes up pretty high, unlike 2" that are usually in strong breakup mode to get something that measures flatish past 10khz.

www.electrovoice.com/downloadfile.php?i=1703
electrovoice.com/downloadfile.php?f=HR90%20EDS.pdf

I'd run an active crossover if I were you, but look for cd-eq on it and you may need to build a small network to boost the highs even more. Very tricky stuff to do all passively, especially with the horn/driver Zspikes.

Jbl ran a 2344 horn in the 4430 loudspeaker (2-way).
4430/35
the 4430 DIY thread

To me, you want a horn that keep directivity down to the crossover point. I like 40x90 dispersion, but I lose vertical directivity below 2khz. So I may have a dip 750hz - 2khz in the far field due to it losing di. Nice place to have a dip.

The 500hz horns (behind some movie screens) require 3' x 3' horn mouths to keep directivity all the way down to the crossover point. That's bigger than most people's bass horns.

Norman

[Inductor]

Originally Posted by bassnkeys

I have a pair of 2418h drivers and bi-radial horns I'd like to use in a two way design. I don't need to get high sound pressure levels from them... home not pro use. How low can I go with a crossover point? Opinions? Experiences?
Thanks,
bassnkeys in MN

You have the JBL 2374 HF horn for a crossover frequency of 1300Hz with the
JBL 3722/3722N Two-Way ScreenArray Cinema Loudspeaker System.
http://www.jblpro.com/catalog/suppor...pe=3&docid=620
JBL 3722-HF | Performance Audio
Audio Profesional Bocinas
http://www.jblpro.com/pub/cinema/3622N.pdf
???????????? : JBL 3731

About a 3-Way (3731):
http://cn.jblpro.com/catalog/support...pe=3&docid=618
The semi clone of JBL 3731's build thread - AVS Forum

You have good information from various combos from Wayne Parham also.
Pi Speakers - Product Measurements and Datasheets
Others
Best Horn for JBL 2426H Driver?