New 1.5" Beryllium CD from 18Sound

[SunRa]

Wow, have you guys seen this: ND4015BE - HF Neodymium Driver ?

4" Be diaphragm! I have the strong feeling that when that day when I'll build my speakers, I'll use 18Sound drivers.

An externally hosted image should be here but it was not working when we last tested it.

It would need some Eq, that's for sure, but 600Hz to 20Khz seems now possible. Is it me or I see some resonances in the impedance curve?

An externally hosted image should be here but it was not working when we last tested it.

 

[SunRa]

Oh my.. I've seen the price. My hopes are ruined..

1,650 EUR each.. I really thought a production model Be driver would be cheaper than modifying a CD with Truextent diaphragm.. Man..

 

[pos]

I wonder if these diaphragms come from truextent or not.
Even JBL sources its bare diaphragms from truextent (and add its own voice coil).

The impedance of this 18sound sure looks nice, with no rise in the UHF (that said, rising impedance is not a problem at all with active crossovers...)

 

[SunRa]

Yeah, I was wondering about that also.

Anyhow, these seem to be some of the nicest CD's available. If they sound as good as they look and measure..

 

[RockLeeEV]

Anyone know the exit angle?

 

[pos]

No exit angle per se: it is a throat-less design.
I think it should be considered 0° for horn mouth calculation.

 

[SunRa]

Aren't the 1480 and 2060 from 18sound of similar construction? And I've noticed people specified exit angles for them:

"18sound 1480 = 10 degrees, 2060 = 18 degrees" from another forum

 

[superlian]

I had jbl2450sl with Truextent before and Now i bought a brand new pair 18sound nd4015be.

This is my initial measurements. I use high pass 400 Hz 48 dB in the active crossover under the measurements and always a 47 uF capasitor for protection.


Imgur: The magic of the Internet

Imgur: The magic of the Internet

Imgur: The magic of the Internet

 

[ErnieM]

Thanks for the measurements!

Distortion does indeed seem very low for a compression driver.

How does it compare to the JBL’s?

 

[superlian]

I havent played with it yet. Just done some measurement.
The frequency response are smoother with Jbl.

 

[phase_accurate]

Vance Dickason has tested that one:

http://www.eighteensound.com/Portals/0/Download/VoiceCoil_Feb2014_ND4015BE_low.pdf

Much cheaper but seemingly also very nice from the measurement data is the following one, if one can live with 1.4" and a crossover frequency of 1 kHz:

Test Bench: Eighteen Sound ND3ST 1.4” Compression Driver | audioXpress

Regards

Charles