[jeffx]

Jeff,

What are your recommendations for upgrades to my KEF 104/2 crossovers? I am looking for more clarity. Thanks for any help.



Original image with pic of an actual xo can be found here - - > https://imgv2-2-f.scribdassets.com/img/document/266612771/original/d3f5736b07/1464741870

[Jeff]

Hello,

One of the first things to do is to confirm your XO is identical to the one in the link.  If not, how do they differ.  Budget?

[S Clark]

Wow.  I've seen a lot of crossovers, but that's just about the most involved XO I've ever seen.  Not trying to take business away from Jeff, but it might be more cost effective to have Danny R or someone like him simply design a new one.  I mean really, 4 caps and two coils... just on the tweeter???

[jeffx]

Here is an actual pic of mine. The values all appear to be the same as the one above. Let's put the budget at $750. Can go higher if necessary, but upgrades will need to be done incrementally.

[Jeff]

Wow.  I've seen a lot of crossovers, but that's just about the most involved XO I've ever seen.

Oh...  That is nothing.  This network is not even close to the title of "More $hit in it than a Christmas Turkey"   Eight of the components are paralleled pairs to adjust value.

Not trying to take business away from Jeff, but...

No problem.  That is the beauty of 2016....lot of options   However, your suggestion "might" lack a little tact in my circle.

it might be more cost effective to have Danny R or someone like him simply design a new one.

Maybe not here.  You would have to add shipping at least one speaker half way across the country, and back to the bill.  Only one speaker would not allow for proper voicing.  A simpler network may not be possible/superior.  Danny does not work for free.  The OP did not list anything about a desire to alter/rotate phase.  This would be further complicated with the very real chance the speaker is damaged in shipping.  However, I do have confidence in Danny's abilities

  I mean really, 4 caps and two coils... just on the tweeter???

A 4th order on a tweet is not all that uncommon.  Two of the caps are in parallel, and make for a single cap position.  The second cap position is separated into two positions to allow a little shaping.

[Jeff]

Here is an actual pic of mine. The values all appear to be the same as the one above. Let's put the budget at $750. Can go higher if necessary, but upgrades will need to be done incrementally.

You are plenty good.  The budget merely mitigated whether we improved the detail on a the cheap, or improved it the flavor I would want for myself.  I'll work you something up.

[S Clark]

I'm sincerely sorry, Jeff.  I didn't realize that you did crossover design.  I was thinking that you could make a sale of the parts.  I'd never try go on anyone's circle to poach business for a competitor.  Also, I should have caught that those caps were paralleled to get to a specific value.
Again, please accept my apologies.  I've bought from you several time, recommended your products to friends, and have always been very happy with the results. 

[Jeff]

I'm sincerely sorry, Jeff.  I didn't realize that you did crossover design.  I was thinking that you could make a sale of the parts.  I'd never try go on anyone's circle to poach business for a competitor.  Also, I should have caught that those caps were paralleled to get to a specific value.
Again, please accept my apologies.  I've bought from you several time, recommended your products to friends, and have always been very happy with the results.

I do not believe that was your intention, so there is no need for an apology.  Thank you for your business, and kind words

BTW, "GR" once stood for Glowacki/Richie.  As in Jeff Glowacki/Danny Richie 

[Jeff]

Here is an actual pic of mine. The values all appear to be the same as the one above. Let's put the budget at $750. Can go higher if necessary, but upgrades will need to be done incrementally.

OK, you are looking for "clarity".  It won't be hard here.  Your XO is full of electrolytics.  Old ones to boot!  And, while your Kef is warm without aging lytics, just slamming film caps in there might have a rather "White" result.  If not bright.  I'm assuming that you are looking for more than detail.  Transparency, etc...  Given your budget, this is what I would do:

-Replace C1 with: http://www.soniccraft.com/product_info.php/gen-sonicap-uf-200vdc-p-444
-Replace C6 and C7 with: http://www.soniccraft.com/product_info.php/mundorf-mcap-evo-oil-100uf-350vdc-p-4175
-Replace C8 with: http://www.soniccraft.com/product_info.php/gen-sonicap-25-uf-200vdc-p-461
-Replace C12 with: http://www.soniccraft.com/product_info.php/gen-sonicap-43-uf-200vdc-p-432 (request 4.2uF).
-Replace C13/C14 with a single high value: http://www.soniccraft.com/product_info.php/dynamicap-7uf-210vdc-p-156
-Replace C15 with the following paralleled combo of three caps: 2Xhttp://www.soniccraft.com/product_info.php/dynamicap-7uf-310vdc-p-157 + http://www.soniccraft.com/product_info.php/pair-kimber-kap-22uf-200vdc-p-5118  The Kimbers are already a pair, so you will only need "1" for your project.
-Replace C16 with the following paralleled pair of caps: http://www.soniccraft.com/product_info.php/dynamicap-5uf-210vdc-p-4879 + http://www.soniccraft.com/product_info.php/dynamicap-5uf-310vdc-p-167

This recommendation will come in under your budget with almost enough left to purchase all the other electrolytics.  The only limitation here is that the Dynamicaps and Kimbers are on closeout.  I barely have enough stock to satisfy my recommendation above.  Questions?

[jeffx]

Thanks for the quick recommendations.

Should I request matching on any of these? If so, what level? Are you are using 210v and 310v Dynamicaps because of the quantity available? Should I be concerned with replacing any of the resistors?

[Jeff]

Should I request matching on any of these?

No, you get that for free on this deal

Are you are using 210v and 310v Dynamicaps because of the quantity available?

Yes, and the necessary value.  Hence, the free matching.  I had to see what we had

Should I be concerned with replacing any of the resistors?

Not in this case.

[Enikma]

Hey Guys,

Thanks so much for this post. I have recently pickup up a set of Kef 104/2 and  would like to restore them to the former glory. Possibly even beyond this.

I was wondering what the outcome was in relation to sound quality with the upgraded crossovers?

Did you manage to go through with them Jeffx??

Thanks in advance

Nik 

[dublin78]

+1

[Stimpy]

The tweeters that KEF used on the 104/2's contained ferrofluid.  The type of fluid used, is notorious for drying out and hardening, which gums up inside the tweeters.  It's also advisable to clean the tweeters and replace the ferrofluid, as well as recapping the crossovers, when restoring these speakers.  If damaged beyond repair, Midwest Speakers offers a drop-in replacement, for the KEF tweeters.

https://www.midwestspeakerrepair.com/shop/home-audio/tweeters/dome/mw-audio-mt-1191-1-inch-dome-tweeter-for-kef-104-2-speaker/

Also, the Morel MDT-29-4, 4ohm tweeter is a good replacement.  But, it's harder to find in the 4 Ohm version.  Plus, the tweeter mounting posts, in the speaker, requires slight modification, for the Morel's to install.