Early KLH Sixes - Question!

jgannon

AK Subscriber
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Ok, I just responded to a thread regarding KLH Sixes, and thanks to Glenn (GD70) he informed me that the grill I had on the speakers was not original, nor were the handles that were haphazardly attached to the back of the speakers (one was attached to the top of one, and to the bottom of the other).

Heres' how the speakers looked (I got these a little over a year ago):

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I removed an inner beveled frame, that might have been built by one of the owners, and removed one of the grills. This is what it looks like:

20170313_114912.jpg

I was just wondering - would these be the original drivers?
 
Here is a close-up of the tweeter and woofer of the first speaker. I pushed the woofer in a la Glenn's advice, and it came right back, so the surrounds will need attention.

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I took the grill off the other speaker, and it looks like the tweeter is the same, but the woofer is different. So, was this woofer replaced? Do any of these look like the original drivers?


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I think they appear to be very early models Sixes. The blue-glue ring around tweeter is a bit strange, These would be a challenge to install non OEM drivers since the are glued to baffle board.
 
Those are original drivers. You've got to remember that back then in the early days of KLH, everything was made in house....the cabinets, the crossovers, the speaker drivers. It's not unusual to find two similar, but different looking drivers in those early KLH speakers. They were probably made during different production runs, hence the differences. Alternatively, one of them may have gone back to the factory for repairs at some point and they removed the original driver and replaced it with an updated one. And yes, those drivers are epoxied in there from the factory. They knew how to get them apart back then for repairs......so its not unheard of.
 
Those are original drivers. You've got to remember that back then in the early days of KLH, everything was made in house....the cabinets, the crossovers, the speaker drivers. It's not unusual to find two similar, but different looking drivers in those early KLH speakers. They were probably made during different production runs, hence the differences. Alternatively, one of them may have gone back to the factory for repairs at some point and they removed the original driver and replaced it with an updated one. And yes, those drivers are epoxied in there from the factory. They knew how to get them apart back then for repairs......so its not unheard of.


The serial # on the speaker with the darker woofer is #28881 and the serial # on the speaker with the lighter woofer is #24193.

I'm trying to figure out if the woofers need new surrounds. They do spring back when I push them in, but upon closer examination, I can see them ever so slightly taking a little time. I'm not sure!!!

If I had to get in there, I'm imagining it would be a big ordeal to get the tweeter off that baffle.
 
You don't need new surrounds. Probably just need to "re-dope" them. There is a fellow on ebay that sells the proper stuff. I believe his user name is "vintage-ar". Being that these are the early epoxied version, your crossovers most likely have the oil-filled capacitors, so you really shouldn't have the need to ever open up the cabinets, unless you are currently having issues with the drivers.
 
You don't need new surrounds. Probably just need to "re-dope" them. There is a fellow on ebay that sells the proper stuff. I believe his user name is "vintage-ar". Being that these are the early epoxied version, your crossovers most likely have the oil-filled capacitors, so you really shouldn't have the need to ever open up the cabinets, unless you are currently having issues with the drivers.
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Hey thank you. I was hoping that I wouldn't have to attempt to break into the speakers. I mean they sound very good now. I don't know if they could be taken to even greater heights, so to speak. But I have no complaints about them really as they are.
 
KLH Sixes are arguably one of the best speakers ever made. Henry Kloss himself said in an interview once: "we got it right with the Model Six". Can't ask for much more than that can you? ;)
 
I have some early model Sixes, but not that early. Mine were the type that had the woofers/tweeters in the front baffle too. They are in the 61000 serial number range and definitely didn't have oil caps. I'm wondering if anyone out there can confirm oil caps with serial numbers so we could localize if you might have oil caps too. I would wait to open them up pending some response that would help with this if they are working well. If you have oil caps then you might be good to go for a while without recapping them.

I can confirm they are sweet sounding. I recently restored mine and they are my favorite. I've just rotated in a set of Original Large Advents (OLA's) that haven't been recapped yet and the Sixes are clearly much much better. Now I have to recap and perhaps upgrade the OLA's to see if they can get closer to the Sixes.
 
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Some where among the many threads on Sixes, it was stated that oil filled caps were only used in the first year or two of production, and could not be linked by serial numbers. It's also my understanding that oil filled caps will not drift off spec, so no need to hack into the back. To the OP, if they sound good, leave them be, IMO. Enjoy.
 
Generally the give away of bad caps in the KLH's were either dead or partially working tweeters. I had a set in the 20K range serial #'s and the tweeters worked perfectly. If your tweeters are singing, I'd say you've got the oil caps. Just brush on the sealant (dope) onto the surrounds and you'll be good to go. Iconic speakers for sure!
 
Generally the give away of bad caps in the KLH's were either dead or partially working tweeters. I had a set in the 20K range serial #'s and the tweeters worked perfectly. If your tweeters are singing, I'd say you've got the oil caps. Just brush on the sealant (dope) onto the surrounds and you'll be good to go. Iconic speakers for sure!

You don't need new surrounds. Probably just need to "re-dope" them. There is a fellow on ebay that sells the proper stuff. I believe his user name is "vintage-ar". Being that these are the early epoxied version, your crossovers most likely have the oil-filled capacitors, so you really shouldn't have the need to ever open up the cabinets, unless you are currently having issues with the drivers.

Thanks again, guys. I was just wondering - from the pics I posted would you say the surrounds definitely needed sealing? I could take some closer pics if you aren't 100% sure. I've never resealed any speakers, so I wouldn't want to do it if it weren't necessary. But then again, I'd want to get the most out of the speakers that I could. I've also read you have to be careful not to put too much of the sealant on, but I guess that's another topic.
 
The darker woofer cone may indicate these were sent to KLH for repairs. Back in the day, the only way into the cabs was through the woofer cone, which would have to be replaced. I've never seen a smooth, black cone on Sixs of this vintage. I suspect you could have oil caps. I've read but I'm a little fuzzy, oil caps were used up to 20k serial number range. Mine are from 1963 and did not have oil caps. Interestingly, one of mine has the screw mount tweeter, the other glued like yours. My serial numbers 068100 & 064162. This is the year the screw mounted tweeters were phased in. With the permanently glued grill cloth, you would never know as they sound identical. I got mine from the original owner who was planning to toss them in the trash. I fully restored them, and they sound fantastic!
 
Yes, definitely reseal
Thanks again, guys. I was just wondering - from the pics I posted would you say the surrounds definitely needed sealing? I could take some closer pics if you aren't 100% sure. I've never resealed any speakers, so I wouldn't want to do it if it weren't necessary. But then again, I'd want to get the most out of the speakers that I could. I've also read you have to be careful not to put too much of the sealant on, but I guess that's another topic.
After nearly 60 years, it's going to be dried out. The sealer is very easy to apply, just brush on a thin coating quickly with a small utility brush. Takes a few minutes. The sealer will stay tacky for many years, so basically you can listen to them the next day.
 
Yes, definitely reseal

After nearly 60 years, it's going to be dried out. The sealer is very easy to apply, just brush on a thin coating quickly with a small utility brush. Takes a few minutes. The sealer will stay tacky for many years, so basically you can listen to them the next day.

Ok, cool. I'll look up that vintage-ar site. Thanks.
 
Someone on AK said that you don't need to make them airtight - just substantially sealed per a push test. (Maybe it was GD70?) That's so you don't go heavy with the dope because that will hurt the bass too. Also have good ventilation when applying. It's easy to apply and takes about 5 minutes.
 
Someone on AK said that you don't need to make them airtight - just substantially sealed per a push test. (Maybe it was GD70?) That's so you don't go heavy with the dope because that will hurt the bass too. Also have good ventilation when applying. It's easy to apply and takes about 5 minutes.

You know, I read that on the fly on my smart phone today from an older thread. I read how one guy, put the sealant on and that happened. I'd like to hear another pair of Sixes to get an idea, if these are doing all they can. My feeling is that if by any chance they aren't, they're pretty darn close. The tweeters have a nice open sound. But I don't know if the bass could go deeper or not. I mostly have them hooked up to a Fisher 800B. But back around the holidays, I hooked them up to a Sony 6060 receiver (solid state) and on a couple of CDs, those Sixes really resonated down in the bass, in a way I hadn't heard them do it before. So maybe they're alright.
 
You know, I read that on the fly on my smart phone today from an older thread. I read how one guy, put the sealant on and that happened. I'd like to hear another pair of Sixes to get an idea, if these are doing all they can. My feeling is that if by any chance they aren't, they're pretty darn close. The tweeters have a nice open sound. But I don't know if the bass could go deeper or not. I mostly have them hooked up to a Fisher 800B. But back around the holidays, I hooked them up to a Sony 6060 receiver (solid state) and on a couple of CDs, those Sixes really resonated down in the bass, in a way I hadn't heard them do it before. So maybe they're alright.
Simple enough to do the woofer test and see. Feel the surrounds. Are they tacky, or dry?
 
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