Tim D
Super Member
I live a couple of houses short of the end of a cul-de-sac. We’re out from town a few miles and in fact we’re under county jurisdiction. The lots here are big at about 1.5 acres. It’s a sleepy neighborhood on a dead end street. Most of the neighbors are older and there isn’t a lot going on except for the occasional yard work. More neighbors here are retired than are still working. Once in a while, instead of driving out of the neighborhood, I turn the other way and drive to the end of the cul-de-sac just to see what’s new. Rarely do I see anything special, but this day was different. As I looked at the last house, I noticed something stacked by the curb, as I drove closer I saw that it looked like some speakers with some items stacked on top. I stopped the car to take a closer look. It was a couple of speakers along with some Sony thingy and a vacuum tube which-a-ma-jig by the looks through the grill on top. I popped the hatch on my car and started shoveling the items into the back. I’ll be darned if I’m going to let that garbage truck dine on these poor neglected audio soldiers. My wife was sitting in the passenger seat wondering what I was up to. Not understanding at all what I had found (btw, she still doesn’t understand, but she humors me).
After we were home I did some research on the find and found that what I had was:
2 - Early model KLH 6 speakers (Flush terminal plate and sealed woofers)
1 - Sony CD Player (CDP-31)
1 - Dynakit Stereo 70 Power Amplifier (In rough non-restored condition)
After doing some online research and finding AK I saw that the KLH and the Dynakit were sought after items. (I haven't even researched the CD player, but I suspect it is run-of-the-mill or lessor). I've since done lots of reading on AK and CSP. Seems that I have the dreaded "KLH 6 sealed cabinets/speakers". I've also found out that all is not lost. There are ways to restore these speakers even with the noted difficulties.
I haven't contacted the neighbor who left them out yet, but I will. I'm curious about the history of these items. Following is a more detailed description of what I know about these twins.
The speakers have been worked on before.
I quickly found out that I had early model KLH 6 speakers. All was not well though. The prognosis was that these had a hereditary disease call the “dreaded KLH 6 sealed speaker” syndrome with the prognosis that they could also come down with chronic capacitor failure. All is not lost though. The doctors at AK and CSP had prescriptions for treating these conditions. And so the treatment begins.
The serial numbers for the twins are 061114 and 061769. Someone else had tried to treat the chronic capacitor failure. I found that the original grills had been cut off and the tweeters had been replaced by RS 40-1289A Midrange Tweeters with a more recent style (electrolytic?) capacitor in series. After removing one of the transplanted tweeters, I saw inside that the original main cross-over capacitor (2x4 uF) was still dangling at the end of a disconnected wire. The original surgeon had left some loose ends. While I can’t confirm it, research would seem to indicate that the hole in the front baffle that was holding the RS tweeter was not original. That hole is not counter-sunk as I have seen in the later model KLH 6’s. The hole was not perfectly circular either – but not badly out of round. I am thinking there were sealed tweeters in these cabinets at one time and that the previous owner(s) had diagnosed a failed tweeter/capacitor and done some surgery to correct the problem. The end result was that the original tweeter was replaced by a transplanted RS tweeter and some unknown cross-over work had been done. Here is the result of the triage on the twins.
Front Baffle – See previous paragraph. We have a hole for the tweeter that probably wasn’t original.
Grills - Since the original grills were gone, the previous owner(s) had replaced them with some black waffle texture foam grills. These were the kind you could buy and cut to size back in the 1970’s. Needless to say the badges were gone too.
Original tweeters – Gone.
Cross-over condition – Unknown, but working at some degree. There’s an obvious need for some surgery here to stabilize the patient.
Cabinet Veneer – Not fatal, but there were some scratches, a couple of chips, some dinged corners and one of the twins had the dreaded “water ring” on top. A likely attack by a beer bottle or some other drink sized vessel. Overall though they looked very restorable, but it was going to take some work. There will be some challenges.
Woofers – Look to be in great shape for being +50 years old. I am aware of the need to seal the cloth surrounds per the direction of the various doctors at AK and CSP. These woofers look like they hadn’t been touched since they left the factory. I.e. No one had ever re-sealed them. They look to need some surface cleaning too.
Terminal Plate – A little corrosion here. Also since they had A, B and C connectors and came with a jumper between B and C, I noticed that the jumpers were missing.
To perform the surgery I’ve begun collecting the tools and donated organs to resuscitate the twins. Here’s where I’ve gone so far.
Overall, I’ve had fun writing this up. I’ve done a lot of research, but I’m going to need some help when it comes to the wood restoration. I simply don’t have that experience. I have read many of the posts on this topic for various KLH models and I’ll take those under consideration before I start asking questions. I also might need some guidance on the finer details of the restoration such as grill and badge replacement options and whether my choice for tweeters was the best approach. I would have liked to verify whether the original tweeters were the sealed type and whether I might be able to find the original sealed type tweeters. The tweeters I bought were apparently from a model 22. Not sure if those are appropriate for the Model 6 or not. I’d also like to know if anyone has any thoughts on the difficulty in finding another jumper for the B and C terminals.
Any thoughts?
Tim D.
Melbourne, FL
P.S. I think I can deal with the cross-overs. I know that I have to go through the terminal plate in the back and chip out the potting material. I will be able to mostly figure that out. I’ll have to cleanup that back plate and the switch. I’ll get some cleaner for the switch.
After we were home I did some research on the find and found that what I had was:
2 - Early model KLH 6 speakers (Flush terminal plate and sealed woofers)
1 - Sony CD Player (CDP-31)
1 - Dynakit Stereo 70 Power Amplifier (In rough non-restored condition)
After doing some online research and finding AK I saw that the KLH and the Dynakit were sought after items. (I haven't even researched the CD player, but I suspect it is run-of-the-mill or lessor). I've since done lots of reading on AK and CSP. Seems that I have the dreaded "KLH 6 sealed cabinets/speakers". I've also found out that all is not lost. There are ways to restore these speakers even with the noted difficulties.
I haven't contacted the neighbor who left them out yet, but I will. I'm curious about the history of these items. Following is a more detailed description of what I know about these twins.
The speakers have been worked on before.
I quickly found out that I had early model KLH 6 speakers. All was not well though. The prognosis was that these had a hereditary disease call the “dreaded KLH 6 sealed speaker” syndrome with the prognosis that they could also come down with chronic capacitor failure. All is not lost though. The doctors at AK and CSP had prescriptions for treating these conditions. And so the treatment begins.
The serial numbers for the twins are 061114 and 061769. Someone else had tried to treat the chronic capacitor failure. I found that the original grills had been cut off and the tweeters had been replaced by RS 40-1289A Midrange Tweeters with a more recent style (electrolytic?) capacitor in series. After removing one of the transplanted tweeters, I saw inside that the original main cross-over capacitor (2x4 uF) was still dangling at the end of a disconnected wire. The original surgeon had left some loose ends. While I can’t confirm it, research would seem to indicate that the hole in the front baffle that was holding the RS tweeter was not original. That hole is not counter-sunk as I have seen in the later model KLH 6’s. The hole was not perfectly circular either – but not badly out of round. I am thinking there were sealed tweeters in these cabinets at one time and that the previous owner(s) had diagnosed a failed tweeter/capacitor and done some surgery to correct the problem. The end result was that the original tweeter was replaced by a transplanted RS tweeter and some unknown cross-over work had been done. Here is the result of the triage on the twins.
Front Baffle – See previous paragraph. We have a hole for the tweeter that probably wasn’t original.
Grills - Since the original grills were gone, the previous owner(s) had replaced them with some black waffle texture foam grills. These were the kind you could buy and cut to size back in the 1970’s. Needless to say the badges were gone too.
Original tweeters – Gone.
Cross-over condition – Unknown, but working at some degree. There’s an obvious need for some surgery here to stabilize the patient.
Cabinet Veneer – Not fatal, but there were some scratches, a couple of chips, some dinged corners and one of the twins had the dreaded “water ring” on top. A likely attack by a beer bottle or some other drink sized vessel. Overall though they looked very restorable, but it was going to take some work. There will be some challenges.
Woofers – Look to be in great shape for being +50 years old. I am aware of the need to seal the cloth surrounds per the direction of the various doctors at AK and CSP. These woofers look like they hadn’t been touched since they left the factory. I.e. No one had ever re-sealed them. They look to need some surface cleaning too.
Terminal Plate – A little corrosion here. Also since they had A, B and C connectors and came with a jumper between B and C, I noticed that the jumpers were missing.
To perform the surgery I’ve begun collecting the tools and donated organs to resuscitate the twins. Here’s where I’ve gone so far.
- Small jar of surround sealer with brush from “Vintage AR” on ebay. It arrived today.
- A couple of later model KLH tweeters from KLH Model 22 speakers. (I hope they are correct for later model 6’s.) These arrived today.
- A jumper for terminals B and C for one of the speakers. This arrived yesterday.
- Various sandpaper (220 grit and greater), steel wool (0000), laquer thinner, masking tape (blue), brown paper (for the covering the front baffle)
- A soldering gun 30W-130W. (Funny, but I didn’t have one.) Ordered solder to btw.
- Dayton capacitors per the cross-over diagram from the KLH 6 manual available from CSP. (4ea – 2uf, 2ea – 8.2uF. These are 250V)
- Dayton resistors (4ea – 3ohm, 2ea – 7.5ohm. These are 10W)
- Grill parts. Don’t have the fabric or the core right now. That will be last.
- KLH Badges
- Any kind of oil, restoration sealer, laquer, wax, stain, etc
- Any chip repair/filler/epoxy
- De-soldering tool
Overall, I’ve had fun writing this up. I’ve done a lot of research, but I’m going to need some help when it comes to the wood restoration. I simply don’t have that experience. I have read many of the posts on this topic for various KLH models and I’ll take those under consideration before I start asking questions. I also might need some guidance on the finer details of the restoration such as grill and badge replacement options and whether my choice for tweeters was the best approach. I would have liked to verify whether the original tweeters were the sealed type and whether I might be able to find the original sealed type tweeters. The tweeters I bought were apparently from a model 22. Not sure if those are appropriate for the Model 6 or not. I’d also like to know if anyone has any thoughts on the difficulty in finding another jumper for the B and C terminals.
Any thoughts?
Tim D.
Melbourne, FL
P.S. I think I can deal with the cross-overs. I know that I have to go through the terminal plate in the back and chip out the potting material. I will be able to mostly figure that out. I’ll have to cleanup that back plate and the switch. I’ll get some cleaner for the switch.
They look brand new!
