[simoon]

I am building a pair of Jeff Bagby's "Kairos Woofer Modules" for use with my Jeff Bagby "Aurcicle", (RAAL/SB Acoustics) standmount speakers.

These woofer modules are not subwoofers, but designed to create a 3 ways system when used with a standmount/monitor speaker.

The design, for the low pass portion of the crossover (2nd order Lenkwitz-Riley) includes a 5.0 Mh inductor, and a 200 mF cap and a 3 ohm resistor in parallel. The inductor is an laminate core with a DCR of .25. The SB Acoustics 10" woofer is 6 ohms.

My question is, what would the overall effect be, if I replaced that 5.0 mH inductor with an air core with a DCR of 1.2? I guess it would attenuate the bass output, but by how much? And would it do it over the entire range of the woofer's output?


Thanks!

[andyr]

I am building a pair of Jeff Bagby's "Kairos Woofer Modules" for use with my Jeff Bagby "Aurcicle", (RAAL/SB Acoustics) standmount speakers.

These woofer modules are not subwoofers, but designed to create a 3 ways system when used with a standmount/monitor speaker.

The design, for the low pass portion of the crossover (2nd order Lenkwitz-Riley) includes a 5.0 Mh inductor, and a 200 mF cap and a 3 ohm resistor in parallel. The inductor is an laminate core with a DCR of .25. The SB Acoustics 10" woofer is 6 ohms.

My question is, what would the overall effect be, if I replaced that 5.0 mH inductor with an air core with a DCR of 1.2? I guess it would attenuate the bass output, but by how much? And would it do it over the entire range of the woofer's output?


Thanks!

Yes, if the new air-core inductor has a DCR of 1.2 ohms - instead of the 0.25 ohms of the original inductor - you are adding an extra 1ohm in series with the bass signal.  Which, as you say, will attenuate the woofer's output.  How much I'm afraid I can't tell you - but, yes, it will be across the whole FR.

What guage is that air-core inductor - can you get a thicker-guage 5mH inductor that will have a lower DCR than the one you are considering?

Andy