Cornwall II xover upgrade - Help needed, Thanks.

[Gregg357]

I'm replacing my stock "on the terminal cup" xover on a '87 Cornwall II. I bought a set of original "on the wooden board" Cornwall II xovers, that have had the caps replaced with new sonicaps. Attached are photos of the upgraded xovers (pics 1-3). My questions are:

1) You can see one xover has one inductor with a large piece of ferrite missing and the other xover has two pieces of ferrite glued back in place on one inductor. I've been told this will change the values of the affected inductors. I'm sure that is correct. But, what is the practical effect on the sound quality?

2) I have an original (pic 4) xover from the '87 Cornwall II set, if the answer to question #1 requires a replacement of these inductors, can I snip the green ones from the '87 xover and replace the broken red ones on the upgraded xovers?

3) If question #2 is yes, can i reattach the replacement inductors at the end of the old leads, or do i have to attach them all the way to the end down at the tiny terminal strip?

I have done no testing between the xovers as at the moment all components are out as the cabinets are being sanded and stained. I can run audible tests (no testing equipment available) once the cabs are done.

Thanks for any input.

Gregg

Pic 1 of 4 - Both upgraded xovers

[Gregg357]

Pic 2 of 4 - Broken inductor with missing ferrite

[Gregg357]

Pic 3 of 4 - Broken inductor with ferrite replaced and glued

[Gregg357]

Pic 4 of 4 - "On the terminal cup" xover with potential replacement inductors attached

[HudsonValleyNoah]

Gregg, I sent you a PM, Noah

[Gregg357]

Bump for some help, Thanks.

[jambandfan]

Greg, I just rebuilt crossovers from the same model and year with the kit from bob crites. I had the terminal cup as well, and kept everything on the same circuit board, it went very smooth. I would assume that the ferrites broke while being remied from the original circuit board, so be carefule if you do remove them. Now who knows how much this would effect the missing ferrite will have, but I would not want to know that something was not right about something i just put a bunch of effort into. I would consider selling your cornwall 2 circuit boards on ebay, and getting new inductors, which are supposed to be better than stock for both boads from bob, or get the rebuild kit from bob and sell the wooden boards on ebay, with the disclaimer of the broken ferrite. I hope they had a disclaimer wherever you bought them. Good luck -marc

[Guest David H]

You could replace the broken inductors with these. I suspect they are a bit better than the O/E's Your Price: $18.62 EA (1-9) $16.98 EA (10+) Sku 266-912: In Stock Qty: Request a large quantity quote. No Hassle Returns
	http://www.parts-express.com/whyPeNoHassle.cfm'>

[boom3]

what year did the Corn IIs transition from board to "on the cup"?

[jambandfan]

I believe it was in 87 Bob Crites told me that I would have one or the other, depending on when that year they were made.

[Gregg357]

GotHover,

If I replaced the broken inductors with the items you've suggested, would thenew ones play well with the other two older non-broken ferrite inductors, or would I need to put four of the new ones in the xover pair? Thanks .

Gregg

[Guest " "]

if you re-gluded it...I don't think you should worry about it...no current goes thru it....the ferrite mass is used to influence an increase in inductance in the coil. If you could get your hands on an inductance meter you could measure the one with the missing ferrite mass. I don't think there's enough missing to change the inductance values enough to compensate with a steel screw thru the screw hole.