Suggestions for these cheap 15"? Frisbee?

[ßart West-VL.]

I measured one of my old 40-9000 driver from RadioShack / Realistic.
3 out of 4 are still good, 1 has a voice coil that measures way off.
What can I do with these besides using them as a salad bowl?
Measurement was done on only one of them with the added mass method and yes, I thing the result is correct.
Measuring other drivers gave very good results, so these really must be the worst drivers I've ever seen...

[Djim]

Originally Posted by ßart West-VL.

Measurement was done on only one of them with the added mass method and yes, I thing the result is correct.

1425cm^2 for a 15inch!?!

[tomtt]

passive radiators ...

[ßart West-VL.]

oops... now I'll have to measure again, should be 835cm²

[ßart West-VL.]

Looks a lot better but still needs a box of 8000l or 280ft³ for a Qtc of 0.8
With 176l or 6.265ft³, the Qtc is at 1.5 and the response doesn't look half bad now.
-3dB at 32hz and a bump of 4dB at 52hz

Still, suggestions are welcome of course.
Would isobaric turn out well? The efficiency is a bit low for that, I guess.

[Moondog55]

OB bass

[chris661]

Or IB.


I'd stuff all of them in a tiny sealed box, and boost 12dB/octave from the crossover point.

Give it a clean kW of power, and you've got a powerful subwoofer.

[Djim]

Originally Posted by ßart West-VL.

Looks a lot better

It looks more...euh...'realistic' . Btw is that the first measurement from your new measuring system?

[ßart West-VL.]

Lol, good one

First measurement was a B&W 200/4 (8" driver)
Second Visaton FRS8
This 15" was the 'turd' one. haha

Now I'm going to measure the other 15" woofers.
Yes, also the one that has the bad voice coil, could be educational to me.

PR, OB, IB are attractive, I which I had the possibility for IB.
For PR, these drivers aren't worth the extra money.

Thanks.