KLH 6 Cap Replacement Question

[Charles218]

I am attempting to replace the caps in a newly acquired pair of KLH 6's, the tweeters are silent on each speaker. I've tried each tweeter on a working pair of 6's and they work fine. So, I've ordered and received new caps from Parts Express and set out to replace them today. However I was surprised to see that some of the components are buried in, well I don't quite know what to call it, but I can't get to them. Please see the attached photo. Do I just break this stuff up with a screwdriver, or is there a more refined way of getting at these things.

Charles

[speaker dave]

Do I just break this stuff up with a screwdriver, or is there a more refined way of getting at these things.

Charles

I don't know if that is hot melt or something tougher. If it was hot melt you might be able to get it to flow with a heat gun (not a hair dryer). If it is brittle enough to crack with a screwdriver and hammer, then have at it that way.

Remember that you don't necessarily have to remove the old components, but to transfer the connections. (Its your kitchen, no one will ever know. )

David

[Charles218]

I don't know if that is hot melt or something tougher. If it was hot melt you might be able to get it to flow with a heat gun (not a hair dryer). If it is brittle enough to crack with a screwdriver and hammer, then have at it that way.

David

David,

It doesn't appear to be hot glue, I suspect it is before the hot glue era. I may go at it later today, but would like to see if anyone else chimes in first.

Is this normal for KLH speakers? I've not seen it on the few that I have been into, nor have I heard mention of it on this forum.

Charles

[oiseaux]

I don't know if this is in enough time to help out, but I had a similar problem and replacing the single 8 mfd cap in series with the tweet restored its operation.

Within the encapsulation are the switch, a few resistors and two 2mfd caps. I would only chip this apart for restoration if the switch or hi freq select didn't work.

Cheers!

[JKent]

Have not been inside a Six, but ol' Henry WAS fond of epoxy. Take a look at the Model Six manual in the Library. On page 2 it says (in CAPS!):

IMPORTANT NOTE: THE TWO SPEAKERS IN THE MODEL SIX ARE PERMANENTLY SEALED INTO THE FRONT PANEL AND THE FRONT PANEL IS PERMANENTLY GLUED TO THE CABINET. CONSEQUENTLY, NO ATTEMPT SHOULD BE MADE TO OPEN THE CABINET IN ANY MANNER.

How'd you even get in there? Or do you have a later one with screwed in woofers?

I'll bet HK potted the xo to keep your grubby mitts out of it. Henry was a bit of an eccentric.

There's a schematic on page 4: two 2uF caps, one 8uF, two 3.5 resistors, one 7.5 resistor, a 3-way switch and a 0.4mH inductor. With the exception of the inductor, that's identical to the 17, 20, and maybe all the classic KLH 2-ways.

You might just whack that potting material with a screwdriver to break it up and dig all the parts out, as Dave suggested (that's what I would do). BUT, you may very well have to replace the toggle switch if it's too glopped up and probably the resistors, inductor and the terminal screws. Unfortunately, you HAVE to get that out, to access the terminals. What a PITA!

Plan B might be to order terminal cups and all new parts, abandon the original xo and terminals, and do everything new, from scratch. You could use bi-amp cups like this:

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=260-304&vReviewShow=1&vReviewRand=560884

Good luck

Kent

[oiseaux]

Only some of the earliest Model SIXs have the drivers epoxied in. I have 5 from three different iterations of this model and none of mine were epoxied in so I replace the caps easily. Of course, if your DRIVERS are epoxied, I guess you have a tougher problem. But if it is only the crossover parts that are encased, I standby my original advice.

Cheers!