KLH Six circa 1968 Restoration w/Pics!

[GD70]

Bravo Glenn! I've learned so much from your restoration threads, and you've inspired me to take on projects like this. I did the full works to my pair of KLH 23's, and your posts were invaluable. I'd love to find a nice pair of sixes, but they rarely surface here in northern Illinois.

Thank you! Glad I can inspire others to take on these type of projects.

Cheers!

 

[GD70]

Was anyone here expecting a less than stellar job from Glenn?

Glenn, there's room in my bsmt for them, let me know when I can over & remove some of the clutter.

Thanks Kevin, and I may decide to sell them at some point.

 

[GD70]

Nice job Glen! I have a few speakers including my Dynaco a50 that could use your repair technique. Where do you buy veneer? Used to be a place in the Bronx NY that sold veneers.

I found veneer from trashed speakers, furniture etc… also some from AKers reveneering speakers and have sent me the removed veneer scraps.

 

[GD70]

Hey all,

I made a wiring diagram with a couple pics. I've seen a lot of wiring questions and thought this would be a helpful way to show it.
Let me know what you think.

Cheers, Glenn

 

[foundit67]

This is very helpful Glenn. I am new to speaker restoration and have been looking everywhere to improve my knowledge. Your diagram, with descriptive drawing and photos is much easier to understand than anything else that I have found.
By the way, one of my Sixes is missing its third nut, (see photo, no puns necessary, I have a dirty enough mind already). I imagine it is highly unlikely that there is anywhere that I could get a replacement, but I'm asking anyway. I imagine just a nut that fits from the hardware store will do for practical purposes?

 

[RTally]

This is very helpful Glenn. I am new to speaker restoration and have been looking everywhere to improve my knowledge. Your diagram, with descriptive drawing and photos is much easier to understand than anything else that I have found.
By the way, one of my Sixes is missing its third nut, (see photo, no puns necessary, I have a dirty enough mind already). I imagine it is highly unlikely that there is anywhere that I could get a replacement, but I'm asking anyway. I imagine just a nut that fits from the hardware store will do for practical purposes?

The speaker terminal nut is called a Knurled Nut, sometimes a thumb nut or even a knurled thumb nut. You can find them at the big box stores (Home Depot, Lowes) and a well-stocked hardware stores.

Alternatively, you can use a standard nut since that terminal is not used. The nut only needs to clamp the jumper.

 

[foundit67]

Thank you RTally, I'm glad to learn the nomenclature. Do you happen to know the size? I guess I could take one of them off and take it to the hardware store but I don't want to take the chance of losing it.
Cheers, Toby

 

[RTally]

Thank you RTally, I'm glad to learn the nomenclature. Do you happen to know the size? I guess I could take one of them off and take it to the hardware store but I don't want to take the chance of losing it.
Cheers, Toby

If you have any lose screws (not you, in your junk drawer), you can find one that fits and take it with you.

Otherwise, I would remove one and take it with you. If you lose it, buy two.

Or you could do what I often do, buy one that looks about right. When you get home and find out it doesn't fit, go back and get another size.

Alternatively, just buy a bunch of different sizes and have loose hardware around that you cannot find the next time you need some.

 

[foundit67]

All good suggestions. I lose so much time on trifles like this that at my age one wishes for a rebate of time spent on such things. For the small money of course I could buy a couple of sizes that look right. But you have the idea; find a spare nut that fits and take it with me.
Happy Saturday. I appreciate all the advice and good will here.

 

[tnsmnichols]

This is very helpful Glenn. I am new to speaker restoration and have been looking everywhere to improve my knowledge. Your diagram, with descriptive drawing and photos is much easier to understand than anything else that I have found.
By the way, one of my Sixes is missing its third nut, (see photo, no puns necessary, I have a dirty enough mind already). I imagine it is highly unlikely that there is anywhere that I could get a replacement, but I'm asking anyway. I imagine just a nut that fits from the hardware store will do for practical purposes?

Contact AK member @JKent. I’ve purchased exact replacements of these knurled nuts from him before.

*Please note that I have no affiliation with Kent. I’m just a very satisfied customer.

 

[foundit67]

Hey all,

I made a wiring diagram with a couple pics. I've seen a lot of wiring questions and thought this would be a helpful way to show it.
Let me know what you think.

Cheers, Glenn
View attachment 3008909

Glenn, I opened both of my sixes and after reading this and other threads I am now convinced that they should be recapped. My pair has evidence of some recap or earlier repair and the values and brand of the caps looks unfamiliar and off spec when compared to others, but I am no expert, just learning. I'll post photos if you or anyone else is interested.

 

[GD70]

Yes, please post pics! The more we know the better!

 

[foundit67]

Yes, please post pics! The more we know the better!

Wire from tweeter, two caps one after another.

 

[RTally]

Wire from tweeter, two caps one after another.

Of the one where we cannot see the markings is a 16uF, then that is an equivalent 8 uF cap. Series connected capacitance value is calculated the same as parallel connected resisters.

All my KLH speakers had the black body, red ends Temple-style caps. The caps look like they were replaced, but that is sloppy work. The caps should be secured to the cabinet and not left loose, particularly since the wiring is not insulated. I would replace the electrolytics with Metallized poly film caps just because.

 

[foundit67]

Of the one where we cannot see the markings is a 16uF, then that is an equivalent 8 uF cap. Series connected capacitance value is calculated the same as parallel connected resisters.

All my KLH speakers had the black body, red ends Temple-style caps. The caps look like they were replaced, but that is sloppy work. The caps should be secured to the cabinet and not left loose, particularly since the wiring is not insulated. I would replace the electrolytics with Metallized poly film caps just because.

Thank you very much for your experience and thoughtful advice. This is a new subject for me and I have never soldered a wire before in my six plus decades on this earth so your help is very much appreciated. Yes, the other cap is the same value. In both speakers they were just hanging there with no support.

In this photo you will see a blank with a clip where there once was, perhaps, the original cap?

And you suggested "metalized poly film caps". Do you have a favored brand and seller?

Cheers,
Toby

 

[GD70]

Thank you very much for your experience and thoughtful advice. This is a new subject for me and I have never soldered a wire before in my six plus decades on this earth so your help is very much appreciated. Yes, the other cap is the same value. In both speakers they were just hanging there with no support.

In this photo you will see a blank with a clip where there once was, perhaps, the original cap?

And you suggested "metalized poly film caps". Do you have a favored brand and seller?

Cheers,
Toby

Yes, there was an 8uf cap there originally. Also odd that red cap or resistor embedded in the epoxy.

 

[foundit67]

Yes, there was an 8uf cap there originally. Also odd that red cap or resistor embedded in the epoxy.

Glenn,

Well this is an adventure! I'll be breaking up that epoxy so I recon we shall see just what that "odd cap or resistor" is. In the meantime I am researching/looking for a better than average soldering iron, (Stahl Tools DDSS looks good), 60/40 solder, Dayton caps, etc. Game on!

The fiberglass chunks in both speakers smell awful from age and mold. I'm going to replace it. I'm tempted to use something different for an acoustic barrier. I'm not a fan of fiberglass although I understand it is original to the speakers.

The cabinets themselves are in pretty rough shape. I am still kicking that can down the road though. I want to hear the end product as intended before committing to that.

Cheers,
Toby

 

[GD70]

Glenn,

Well this is an adventure! I'll be breaking up that epoxy so I recon we shall see just what that "odd cap or resistor" is. In the meantime I am researching/looking for a better than average soldering iron, (Stahl Tools DDSS looks good), 60/40 solder, Dayton caps, etc. Game on!

The fiberglass chunks in both speakers smell awful from age and mold. I'm going to replace it. I'm tempted to use something different for an acoustic barrier. I'm not a fan of fiberglass although I understand it is original to the speakers.

The cabinets themselves are in pretty rough shape. I am still kicking that can down the road though. I want to hear the end product as intended before committing to that.

Cheers,
Toby

Regarding the fiberglass, I’m of the school to use same or similar to what was original. Others will have opinions regarding new poly fill vs. new fiberglass, and if the sonics are altered. Important to measure the weight of the original fiberglass to keep the same with replacement. Poly fill I think will be lighter, so may require more?

 

[foundit67]

Chipping away... and wondering what you think of that big red cap. I have entered the world of the unknown, (to me), here. I imagine that I have to carefully remove most, if not all of the "candy" around the wires that I will need to access.

By the way, Happy Christmas har har jolly New Year and all that...

Cheers, Toby

 

[GD70]

Chipping away... and wondering what you think of that big red cap. I have entered the world of the unknown, (to me), here. I imagine that I have to carefully remove most, if not all of the "candy" around the wires that I will need to access.

By the way, Happy Christmas har har jolly New Year and all that...

Cheers, Toby

The red cap appears to be the two 2uf caps packaged together. Haven’t seen a cap like this before now. Almost always the black temple caps. Can you peel off the remaining tape there so we can see the values printed on the cap?

Happy holidays to you too! Cheers!