New Celestion "AxiPeriodic Driver"

Before I start to come across as a RCF fanboy, I am not.

Whilst the ND series are overall very good, I wouldn't buy their older RCF ND3020 driver.
Even the 850 series can sound harsh, especially with the all-metal diaphragm.

Similar to the B&C drivers:
 

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The reason why all-metal diaphragms remain popular, has to do with the prolonged high output levels common in PA.
Mylar/Polymer suspensions are subject to softening, or even melting due to the heat generated by the :magnet: system.

"...And that's why these are called soft-suspensions" :faint:
 
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No, unfortunately JBL does not deem it necessary to design horns (for compression drivers) that work below 800Hz, since the introduction of the PT horns.

If you don't mind a very narrow dispersion, this one's cut-off is at 400Hz:

cEqNeRfh.jpg



It's a clone of the Selenium HL4750-SLF, which is essentially a modernized JBL 2386, a Flat Front Bi-Radial 40° H x 20° V horn,
designed to be used with 2441, 2445, 2446, 2450 2" drivers.
I am not sure if it works with your drivers, but some members of the Klipsch Forum like it a lot.

And so do the people from G.I.P. Laboratory, apparently (it's in the speakers with the silver (Selenium?) bullets on top):

N6sagQfh.jpg


CU5wynAh.jpg
 
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At RCF they know a thing or two about horn design too.

Take the H100 for example.
Below is a page from a 1990's RCF catalog, even the old N481 is included.

Today, the H100 is still one of the very best horns for 1" drivers.
Some people prefer it to the SEOS and the famous QSC PL-000446GP waveguides,
because the H100 REALLY doesn't sound like a horn.
 

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In the past, I have contacted several Chinese suppliers.
Clone drivers are available for next to nothing: DE250 for $5-10 each, DE500 for 20-25, etc.
However you'll have to place bulk orders. Shipping individual units is quite expensive.

I was tempted to buy a pair of these though, with both diaphragms:
 

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The JBL PT clone horns above, are probably better than the original JBLs.
The throat is completely smooth, whereas the JBLs have tiny diffraction slot.

attachment.php



You would probably have to polish some rough edges, leftover from the molding.
 
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