Eminence coax, how low can it load a compression driver?

[FE3T]

I have looked at several of Eminence`s coaxial speakers and wonders how low one can expect these coaxes to properly load a compression driver?

The KL3012CX-8 looks very interesting, but crossing it at 2,5khz seems a bit high, especially since i already have a pair of JBL 2425HS drivers in good condition. and as far as i know JBL has used these down too 1,2khz in their biradial horns. I have also a pair of B&C DE250-8 which I have seen used down to 1,6khz with claims of decent sound. (adapter necessary)

So to cut it short, how low can I let my compression drivers play before these coaxes becomes a problem.

PS hifi use with subwoofers.

 

[GM]

This is just a woofer and your CDs are bolt on, so what screw on HF driver specs are you referring to?

GM

 

[cowanaudio]

Your coaxial driver doesn't load the compression driver at all well, that's why you see these high crossover frequencies.

To find out how low you can cross do a THD plot at 10dB below your maximum playback level. This will show you where the driver starts to run out of excursion. Approach this level slowly in consecutive sweeps to ensure you don't smash your driver.

 

[ErnieM]

1.2khz won't be a problem for home use. I wouldn't worry too much about "loading". Most popular waveguides load about the same as a coax of similar size.

Getting your crossover right will be the key to listenable vs. incredible.

 

[cowanaudio]

Getting your crossover right will be the key to listenable vs. incredible.

Getting your crossover right will be the key to unlistenable vs. incredible. 🙄

 

[badman]

The 2425 is a larger format 1" throat. It can be run lower than most other 1" drivers, but that eminence horn is a rinky-dink kinda horn, so I wouldn't push it too much. Usually 2+khz is appropriate for that horn but with the JBL 1.2 should be okay with a decently steep XO (and you'll need a lot of FR shaping, but should have the sensitivity to work with relative to the eminence).

 

[John Busch]

New Emi Neo Coaxes

Currently working up a crossover for the larger 3015. Not as smooth on axis but not all the different off axis relative to the 3012. The 15" will support the right compression driver down to about 1 Khz. So assume the 12" will be OK at around 1.2 Khz, again with the appropriate compression driver. This assumes home Hi Fi use. Add about 400 Hz to the above (give or take) for pro applications.

First impressions are good for the 3015. Dynamic and well controlled. My pair were exactly on spec. Only thing is the cone pictured at the Emi site is smooth, the pair I received are ribbed. Trying them in Open Baffle and large ported box.

 

[FE3T]

This is just a woofer and your CDs are bolt on, so what screw on HF driver specs are you referring to?

GM

The JBL 2425HS are a screw on driver (that's probably why they added the S). and if you read my post again. I did indicate that an adapter was needed if the DE250-8 was to be used.
(probably not a god idea anyway, but an adapter are cheap, and a driver are easily swapped)

 

[FE3T]

Getting your crossover right will be the key to unlistenable vs. incredible. 🙄

I have no trouble believing that it is easy too end up with something unlistenable.
But since I already have and use a minidsp 10x10 in my current system,and also have a 2x4 lying around it should be possible to test a lot of combinations without spending a fortune on crossover components.

 

[ErnieM]

DSP will make it easy to try quasi-linear (or FIR if your hardware supports it) phase crossovers without directivity issues.

I use a Harsch crossover for my 3-way coax system. Measures and sounds great.