123a woofer crossover

[Wallacefl]

A friend has a pair of L-88 woofers and would like me to help him build a 2way diy for fun. I do not want to let the woofer run open like the L-88/100 series but would like to cross it over approx 1500-1800hz. We do not have any measuring equipment and I have searched for a viable crossover ...Troels has 1500 which is unpublished ... Dennis Murphy did a 950 and the S70 Alpha is 1200. The reason for the cut-off desired is that we are going to cross the woofer to a Fountek Pro 5i ribbon tweeter that should not be crossed less than 1500( Stones Audio will help us with the ribbon end).

[Wallacefl]

No one has ever attached an inductor to a 123a/2213...:crying:...and measured the response?

[grumpy]

You could assume 8 or 16 ohms and use any internet crossover calculator.
With just an inductor, it won't roll off very fast (beyond its inherent response),
so being "off" a bit won't matter a lot.

You might try to find an impedance and frequency response plot set for the driver.
It would help.

[badman]

The Le is about .6mH on 123A and so you'll want to incorporate that into your calculation. It's a great woofer to run wide, but you'll want to be careful not to overdo it when designing a crossover, keep in mind that it'll have a narrow beamwidth above 1200hz (where it should be about 90 degrees).