Kef 105/3 crossover concern

[Vorpelsword]

Hi everybody. New to this! This is sort of directed at Speaker Dave from Toronto, if he still reads the forum. I've been reading the forum for the last couple of years and was interested in his comments over a year ago about the 105/3 crossover. I've had my KEF's since new, at least 15 years, and had sort of lost interest in them as they aged, but didn't realise why. Put them to one side for three years. When I realised that I had significant foam deterioration, I refoamed them about a month ago. Great project...I have reams of tips, instructions and photos if anyone is interested. The result is breathtaking. I'm totally back in love with them. The crossovers looked fine, and I have to say that all sounds good but for the fact that the balance is slightly off. All units and tweeters appear to work. I run a cyrus system with monoblocks and can't tweek the balance. It's a speaker problem..tried swopping around etc. The question then (finally) is could this be a crossover problem? ie capacitor degeneration etc. Should I just leave well alone? Speaker Dave was concerned before about attempts to replace capacitors due to specific capacitor and crossover matching in the Maidstone factory. Didn't believe it would be as easy as replacing like with like.What would the forums advice be?
Many thanks.

[PeteMcK]

replace all electrolytic caps

[AllenB]

Normally replacing the electrolytic capacitors is good advice, couldn't hurt either way. Based on Speaker Daves comments, I can see your concern. Generally speaking I would assume that electrolytic capacitors manufactured twenty years ago, and not abused, are probably in good condition.

[Vorpelsword]

Thanks for that chaps. Useful advice and something to ponder on. Should I be grateful for what I have in view of their age, or bite the bullet and rejuvinate the crossovers. Next thing the UniQ tweeters will go! Not that I drink from a half full beer glass or anything... I have to say I'm so impressed by their recovery that I'm happy to keep investing at present.

[AllenB]

Does this look like the schematic of your crossover? Do you feel you can produce something yourself of this level of detail? If not then I'd be reluctant to change drivers.

Your balance problem may be room/reflection related, your listening axis might need reviewing and your placement in regards to bass response might need adjusting to balance the tone.

[Vorpelsword]

Thanks. I've seen this before and it does seem to fit my crossover. If I was going to try anything I'd be aiming to replace components rather than construct. I must admit my listening space is less than ideal, but acoustically sounds surprisingly good. I 'm confident this is a speaker problem though...it moves with the speaker if swapped around. It's only very subtle...but you know how these niggles are!

Really appreciate your input.

[AllenB]

It's just that tailoring a crossover to a driver and its environment (cabinet etc), is a delicate balancing act. Based on my own experiences I'd guess that it took months for professionals with good equipment to agree on the crossover. Anyhow, not to harp.

I'd be suspicious of the crossover components. While in there I'd also refresh any connectors and look for cold solder joints (just precautionary).

I'd measure each resistor against its stated value, and match them left and right. 5% is good. 1% is great.

Look at the electros. Are the cases neat and square? or is there evidence they've attempted to blow open (even slightly). Maybe some discolouration as if they may have leaked? Do you have a means of measuring them?

With regards to the inductors, see that they don't appear scorched. They will probably be fine, and they'll probably show signs if they've been damaged but it is possible that you won't see damage. One relatively simple way of checking them is to measure their resistance. Meters are not usually sensitive at low resistance readings but it will show up anything obvious.

Naturally you may need to pull a lead on some of the components in doing this.

[Vorpelsword]

Thanks AllenB. Good advice. I think I'll have another closer look. May take me a day or two.

[LJNorth]

You say you re-foamed the drivers, unless the foams are a perfect match for the originals this could affect the driver parameters/performance. Have you tested the drivers/speakers with measurement equipment to see this? Without measurements its anyone’s guess as to what’s going on.

[Krabby Patty]

Vorpelsword - you say that "I have reams of tips, instructions and photos if anyone is interested." Yes, I'm interested. Please send to crabypaty2000@yahoo.com Thanks.