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New interesting compression driver

Celestion recently came out with a new compression driver, the Axi2050. For people like me who are interested in large midrange horns covering most of the vocal range (and I'm not talking about the 300Hz-3kHz telephone range, but more like 100Hz to 5kHz), this driver is very interesting. Especially since the high end response is very good for such a large unit. It's more of a mid-high than a midrange driver. Take a look at the frequency response curves, taken from the Celestion data sheet:


The PWT response is only shown down to 100Hz, but it is basically flat down to that frequency. In addition, the HF response looks good up to about 10kHz. That's two decades! And the HF sounds pretty good too; I got a change to hear one such driver on a straight circular Hypex horn at the Celestion factory, and it actually had a nice, smooth high end. Moreover, the driver is rated for 150W down to 300Hz, and the diaphragm is large, so for domestic use, using it down to 100Hz or even lower would not be a problem. 

I would love to try a pair of these drivers on my midrange horns, but unfortunately they are listed as OEM only. Also, I would have to design a new throat and middle segment for the horn, as the driver has 2" exit, and the horn is currently less than 2" in height for about half its length. 

I first became aware of this driver at the 2015 AES convention in NYC, where Jack Oclee-Brown and Mark Dodd presented two papers on the design of this driver: 

Wideband Compression Driver Design, Part 1: A Theoretical Approach to Designing Compression Drivers with Non-Rigid Diaphragms (preprint 9386) and

Wideband Compression Driver Design. Part 2, Application to a High Power Compression Driver with a Novel Diaphragm Geometry (preprint 9391).

At the 2016 AES Convention in Paris, I got the chance to look at the driver itself. It's fairly big, but not very heavy for its size (about 7kg). 

And just for the record: when writing this, I'm still at the university. I'm not trying to sell the driver or to advertise for Celestion, I just want a pair!

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