JBL M2 for The Poors

It's occurred to me that this will probably end up looking a lot like an Econowave. If you took the M2, replaced the dual-diaphragm driver with a JBL 2408H-1, and replaced the trick JBL waveguide with a Pyle knockoff, that's not too far from an Econowave.
Econowave? That's a bit of a backward comparison, don't you think? That JBL waveguide design with a JBL compression driver, and a 15" JBL woofer is more like JRX115 than any econowave, or the M2.

The Selenium was used because it's cheap. I'd add CDX1-1746 to your list of better options for ~2x the price.
 
IMG_20140507_123703.jpg


awwww they're so adorable
 
It looks like JBL has come out with another driver in this series. The JBL 2408H-2. Here's some things I notice about it:

1) The price has been reduced further. The BMS 4540 was made in Germany, cost something like $150. The JBL 2408H was made in the USA. The JBL 2408H-1 is made in Mexico, sells for about $120. The JBL 2408H-2 sells for just $85.
2) It's hard to tell from the pics, but it appears to be about a third smaller than the 2408H-1.

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

Here's a 2408H disassembled. I can't find any pics of the 2408H-2 that I can link to (yet.) Stumbled across it while looking for a 2408H-1 to go with the one I already have.
 
I think that making your own copy of the D2430K would be relatively simple with a 3D printer.

Just use a ring of the 1/2" tweeters from Parts Express, as detailed in the first page of this thread.

I have a box of those tweeters, and the main reason I haven't used them is that they're so tiny, it's hard to build an enclosure for them. They're seriously the size of a pencil eraser.

But with a 3D printer, it's easy to work at that small scale.
 
I think that making your own copy of the D2430K would be relatively simple with a 3D printer.

Just use a ring of the 1/2" tweeters from Parts Express, as detailed in the first page of this thread.

I have a box of those tweeters, and the main reason I haven't used them is that they're so tiny, it's hard to build an enclosure for them. They're seriously the size of a pencil eraser.

But with a 3D printer, it's easy to work at that small scale.

Correct me if I am wrong(again) 8 of those in a series would only ouput 78db MAX spl? Not a lot of dynamic headroom. Headphones? ooh, headphone waveguide project? ;-)

http://www.parts-express.com/1-2-in...source=google&utm_medium=cpc&utm_campaign=pla
 
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Correct me if I am wrong(again) 8 of those in a series would only ouput 78db MAX spl? Not a lot of dynamic headroom. Headphones? ooh, headphone waveguide project? ;-)

1/2" Inverted Dome Tweeter Element 10 Pcs.

The efficiency goes through the roof when you horn load them.

Peerless 830970 2" Full Range Driver 4 Ohm

I'm using a couple of these in my current project. Theoretically, they're good for 82dB. But horn loaded, they're nearly as efficient as my compression driver.

It's trivially easy to increase the SPL by 10dB or more.

Here's an anecdotal example:

The other day I was in a restaurant that was about 1000'. The dude at the counter was using his phone as a boom box. I'm not saying it was hifi, but it was audible all over the restaurant. And that's using a pair of drivers that are similar to the PE drivers. (In his phone.)

So if you're using sixteen of them, face to face, with a proper phase plug, I'm certain it will be much louder than the spec sheet would suggest.
 
Eight face to face with eight, or offset by 22.5 degrees?
will the phase plug origins be at the center of the driver,
or centered between drivers? I mean go ringways a bit,
then turn toward the central plug, the origin still being
at the center of the drivers... You could have up to 32
equally phased vents converging toward center in this
way...