Hi all,

I've had another thread started on help with the box and adding a helper woofer (here) , but I really need some help with integrating BSC.

The speakers: 12" Tannoy CMS 1201 DCT ceiling speakers with no BSC

A basic 2 way with 2nd order low- and high-pass

Stock XO:

1.75 mh series > 25 uf parallel > woofer

6.8 uf series > 0.22 mh & 8.2 ohm parallel > tweeter

First off, I do not have software or measurement equipment. I did look up how to simply add BSC via additional RL circuit, I did add it and it worked. I used components on hand that were close to what the online calculator suggested: 2.3 mh with 5.2 ohm parallel resistor for 6db of BSC, added that in front of the existing passive, then padded the tweeter a little until it sounded balanced.

I'm looking for a more elegant / simpler solution that limits the number of added components in the passive, and hopefully doesn't affect phase like doing what I did.

EDIT: 6db isn't cutting it, I think they really need 8db of BSC.

The cabs are 14.25" wide

Woofer RE is 5.1 ohm

Tweeter RE is 3.9 ohm

Thank you very much to anyone who can chime in and help me pick components to order. I'm going 15ga on the inductor so it's pricey, plus going with Mills resistors. In other words, I'd hate to order more than I need

I've had another thread started on help with the box and adding a helper woofer (here) , but I really need some help with integrating BSC.

The speakers: 12" Tannoy CMS 1201 DCT ceiling speakers with no BSC

A basic 2 way with 2nd order low- and high-pass

Stock XO:

1.75 mh series > 25 uf parallel > woofer

6.8 uf series > 0.22 mh & 8.2 ohm parallel > tweeter

First off, I do not have software or measurement equipment. I did look up how to simply add BSC via additional RL circuit, I did add it and it worked. I used components on hand that were close to what the online calculator suggested: 2.3 mh with 5.2 ohm parallel resistor for 6db of BSC, added that in front of the existing passive, then padded the tweeter a little until it sounded balanced.

I'm looking for a more elegant / simpler solution that limits the number of added components in the passive, and hopefully doesn't affect phase like doing what I did.

EDIT: 6db isn't cutting it, I think they really need 8db of BSC.

The cabs are 14.25" wide

Woofer RE is 5.1 ohm

Tweeter RE is 3.9 ohm

Thank you very much to anyone who can chime in and help me pick components to order. I'm going 15ga on the inductor so it's pricey, plus going with Mills resistors. In other words, I'd hate to order more than I need

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