KLH Model Five -- troubleshooting first steps

[Puddintane]

I just bought a pair of KLH Model Fives from a seller via CL. The seller said that she (and her first husband) were the original owners (bought in Germany, I think it was, circa '71ish). She said they weren't ever played hard or abused (they weren't rockers or partiers). They're in pretty good cosmetic condition and are all original. There aren't any finish problems that a little Howard's won't take care of. The grills are in decent shape (no gaping holes or tears), but, unfortunately, the badges are missing. She had just thrown out the original boxes just a short time ago (Dohhh!). I wasn't able to test them because she didn't have a working amp or source, but I decided to take a chance based on her story.

Unfortunately, when I got them home I discovered that both tweets are non-functioning. And immediately putting them up against my NLAs and my Advent/1s, the sound is not at all what I expected. I've never heard vintage KLHs before and sort of expected something along the lines of my Advents. As they are now, I was extremely disappointed. Much less volume output than either pair of Advents, much less bass and treble, and overall pretty boring. Those are just my initial (and frank) observations.

So what I'm hoping is that someone can give me some guidance on how to proceed to troubleshoot the source of the problem. I'm also hoping that once fixed they'll sound a lot different (and better!). Is there anything I need to be especially concerned with with these particular speakers? As always, thanks in advance for any and all comments and advice!

 

[day67]

Well, don't give up on them. The tweets are replacable if that's what it is. Always available on the ' bay if needed. Crossovers are able to be upgraded fairly easily. I have a pair and they're great but it depends on what your reference speaker is. Others will likely chime in who have immense knowledge. If you need further info check out www.classicspeakerpages, Carl rebuilds the crossovers and is invaluable if needed. If you have basic solder skills you could upgrade these with little difficulty. Caps are available too.

 

[mrjbq]

Bad capacitors can make good tweeters not work. Test the tweeters before you buy replacements. Caps are cheaper than tweeters.

 

[Sharpstik]

I've never heard vintage KLHs before and sort of expected something along the lines of my Advents. As they are now, I was extremely disappointed. Much less volume output than either pair of Advents, much less bass and treble, and overall pretty boring.

I'm not surprised.

I have those and a pair of Original Large Advents. The Klh's have basement duty. And they really soak up power. Even being recapped.

 

[day67]

I cant tell from the pics but the woofers should have a numerical figure on the cones if they ar the original or dedicated approp woofer. Like 24.7 or 25.2, anything like that. I started out with mine being Model 6 woofers in Model 5 cabs. Bigger magnet the big difference. Good news is that the approp parts are available and once the speakers are brought to approp specs they are then able to be given an objective assessment. Worth the effort? Indeed!

 

[jlovda]

About a year ago I bought a pair of absolutely pristine Model 5's from a fellow that also bought them at a PX in Germany. (through CL, for $100) One tweeter was dead and I recapped the crossovers. I love them. The mids and woofers look to be the right type although the woofers do not seem to have the cone weight written on them as DAY67 noted above. The same woofer was used in the Model 12 and 23. Any other woofer would be smaller and look obviously wrong in the mounting hole.

 

[ymarko]

The seller said that she (and her first husband) were the original owners (bought in Germany, I think it was, circa '71ish). She said they weren't ever played hard or abused (they weren't rockers or partiers).

Honest people. The only forgot to mention that they fried the tweeters. And lost badges on these parties.

All drivers should be tested / heard in time of purchase. These tweeters are very easy to hear, they're not some sub-sonic ones. Well worth restoration though.

 

[Puddintane]

Well, don't give up on them. The tweets are replacable if that's what it is. Always available on the ' bay if needed. Crossovers are able to be upgraded fairly easily. I have a pair and they're great but it depends on what your reference speaker is. Others will likely chime in who have immense knowledge. If you need further info check out www.classicspeakerpages, Carl rebuilds the crossovers and is invaluable if needed. If you have basic solder skills you could upgrade these with little difficulty. Caps are available too.

I've seen the stuff at Classicspeakerpages and will probably need some help if I need to do anything substantial. And I've never done crossovers before, and have been planning on trying on something else (in my pile of old speakers) for practice. Looks like I may need to start practicing now!

 

[Puddintane]

Honest people. The only forgot to mention that they fried the tweeters. And lost badges on these parties.

Her (ex-) husband was the audiophile, as she described it. I honestly don't think she'd have known the difference.

 

[Puddintane]

I have those and a pair of Original Large Advents. The Klh's have basement duty. And they really soak up power. Even being recapped.

My amp is a Sansui AU-717. In their present state the KLH's are not even close to sounding as good as even the Advent/1. If they don't improve significantly I'd likely be more than happy to sell or trade them for another nice pair of originals or NLAs.

 

[Puddintane]

I pulled the tweeters and connected them to some speaker wire and they do produce sound, and then I checked them with my DMM and there is continuity, so I'm thinking it's something else. I was a bit surprised to see that the leads coming out of the tweeters (about a 6 in. length of wire) were connected with wire nuts to the wire coming from inside the speaker (from the crossover, I suppose--I didn't yet pull any of the insulation or any other drivers). One unit had two black wire nuts and the other had one black and one ivory colored nut. Is that how these would originally have been connected?

And how do I go about testing the crossovers? This part of the process is all new territory for me.

 

[tubed]

Awhile back I acquired a pair of 10 dollar thrift store Fives. None of the tweeters produced sound 'til I replaced the dead capacitors.
They sounded like $200 thereafter

 

[tmad40blue]

Replace the capacitors. A good majority of KLH capacitors, when they go bad, tend to make the tweeters sound dead. New ones will fix the problem right away.

 

[Puddintane]

About a year ago I bought a pair of absolutely pristine Model 5's from a fellow that also bought them at a PX in Germany. (through CL, for $100) One tweeter was dead and I recapped the crossovers. I love them. The mids and woofers look to be the right type although the woofers do not seem to have the cone weight written on them as DAY67 noted above. The same woofer was used in the Model 12 and 23. Any other woofer would be smaller and look obviously wrong in the mounting hole.

I saw a pair on that auction site, and it gave me the idea to check this: apparently they could be written on the front or rear of the cone.

Edit: just found this, confirms the above: either front or rear.

I think they're all legit enough. Now I just need to learn how to recap the XOs.

 

[biglittledog]

I have a pair of 5's that I recapped and love. It may just not be your flavor but many here like them. If I remember right, the little black capacitors are the culprits for shutting down the tweeters. They suck. Yes the wire nuts are original. You can solder if you want but they should be fine.

There is a good write up I'll try and find on replacing all the caps, not too hard and the trick is to do one at a time. The new capacitors may not look at all like the old ones so no worries if they seem different. I hot glued the replacements in instead of the plastic ties. I have some pics of mine before and after recapping that I'll try and find too. Might take me until tomorrow...
Don't give up on 'em yet!

PS- make a list of the caps on the crossover or count them in the schematic. I'd start out recapping a two way speaker as it's much simpler to do. The parts are pretty cheap so order for your Model 5's and your practice at the same time. Parts Express is easy and fast.

 

[cnolanh]

I also just got a set of KLH Model Fives with the same problem: no tweeter output. Tweeters test fine by themselves, so I have ordered the right capacitors (from Madisound, about $40 total) and will try rebuilding the crossovers. There are good instructions several places online including classicspeakerpages.net, as mentioned above.

Don't judge the speakers before you get the tweeters working! Obviously the top few octaves of music are not being reproduced.

The other thing that can go wrong with these speakers is that the cloth woofer surrounds can shed their sealant dope and become porous to air. When that happens, of course the sealed box is no longer sealed and bass response becomes much weaker. In my case, the surrounds still appear to be airtight (enough) for strong, even bass that gets pretty low. In fact the bass response sounds pretty similar to my Original Large Advents. If you do need to reseal the surrounds, do some searching first to make sure you're using an appropriate substance.

I'll report more when I've gotten the crossovers recapped. Good luck with your set!

Nolan

 

[cnolanh]

BTW, in my speakers the wires to the drivers are also connected with wire nuts, so I'm pretty sure that was original.

 

[Puddintane]

I also just got a set of KLH Model Fives with the same problem: no tweeter output. Tweeters test fine by themselves, so I have ordered the right capacitors (from Madisound, about $40 total) and will try rebuilding the crossovers. There are good instructions several places online including classicspeakerpages.net, as mentioned above.

Don't judge the speakers before you get the tweeters working! Obviously the top few octaves of music are not being reproduced.

The other thing that can go wrong with these speakers is that the cloth woofer surrounds can shed their sealant dope and become porous to air. When that happens, of course the sealed box is no longer sealed and bass response becomes much weaker. In my case, the surrounds still appear to be airtight (enough) for strong, even bass that gets pretty low. In fact the bass response sounds pretty similar to my Original Large Advents. If you do need to reseal the surrounds, do some searching first to make sure you're using an appropriate substance.

I'll report more when I've gotten the crossovers recapped. Good luck with your set!

Nolan

I was just looking at the options at Madisound not five minutes ago. Which brand/size combo did you order? I was looking at the Solens, but they don't offer a 16uF. PartsExpress has the 3, 4, and 25 in the Daytons (no 16). They do list a Solen 16, but, of course, it's on backorder.

Also, my surrounds look to be pretty bare on the cloth. They feel almost like bare cloth, and you can see a lot of light through them. Plus, when I played mine next to my Advents, the bass (and volume level) was, by comparison, practically non-existent.

 

[cnolanh]

I ordered Carli Mylar caps for the smaller values, and a Solen 25uf. The Carli values are slightly off the originals but are well within the 10% acceptable variation.

For the surround: While I had the woofers out, I put my mouth right near the front of the surround and blew focused air strongly right at it. I had my hand just behind the surround and didn't feel anything coming through. A pretty flimsy test, I know, but it confirmed what my ears were telling me. I still may have to recoat the surrounds sometime in the future. Good luck with yours!

Nolan

 

[dodog]

I was just looking at the options at Madisound not five minutes ago. Which brand/size combo did you order? I was looking at the Solens, but they don't offer a 16uF. PartsExpress has the 3, 4, and 25 in the Daytons (no 16). They do list a Solen 16, but, of course, it's on backorder.

Also, my surrounds look to be pretty bare on the cloth. They feel almost like bare cloth, and you can see a lot of light through them. Plus, when I played mine next to my Advents, the bass (and volume level) was, by comparison, practically non-existent.

You're sweating this WAY too much. Just get 1uF and 15uF Daytons, tin the leads, twist them together in parallel, then quickly hit with the iron to solder them together. 16 uF and they stack nicely as the 1uF is tiny compared to the 15 uF.