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Another Seventeen restoration


JKent

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The price was right: Free! I was told these "don't work" and were headed for the curb.

Cabinets are very nice--one or 2 small chips, nice veneer. Grilles are OK. One small stain. They may clean up but I'll probably replace the cloth.

One missing woofer. Bummer. It was replaced with an Oaktron. Never heard of 'em.

Will check remaining 3 drivers and recap.

KLH 17_2 copy.jpg

KLH 17_4 copy.jpg

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Drivers seem fine. Don't know what to do with the Oaktron. Ordered a woofer off ebay. Have the necessary 8uF and 2uF caps on hand so as soon as I free up some time........

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XOs complete and everything works! Will freshen the cabinets soon. A few thoughts:

  • I  really hate the metal back plate. What was Henry thinking?  Considered replacing the terminals with insulated binding posts but in the end kept it "stock". I did check for any shorts with the continuity tester of the Fluke. When reassembling be SURE to install in the correct order. From insice the machine screw goes through the solder lug, then the shoulder washer, then the metal back plate, then the flat rubber washer, lock washer, hex nut, knurled nut. Be sure the screw is isolated from the plate!
  • Don't know why these didn't work (I did not test before hand). The capacitors were not far off. The 8uF cap ws missing from the one with the replaced woofer, so maybe.
  • These seem under-damped. 8 oz FG per box.
  • Finished xo shown below. 2 x 2uF Daytons, 1 x 8uF Carli. It's what I had on hand but the 8uF Carlis seem to be no longer available.

Pics of cabinets to follow.

xo_4 copy.jpg

xo_2 copy.jpg

xo_1 copy.jpg

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Woofer from ebay came today so now they're all assembled. Both woofers failed the push test so I sealed the surrounds with Roy's goo and sealed the dustcaps with diluted Aleene's Tacky glue. Much beter now. These have impressive bass but the HF seems to be MIA.  Checked the tweeters with a stethoscope while playing and they play but roll off. Good candidates for the MicroStatic supertweeters or my home-brews. edit: Duh. Had the HF switch set to Decrease. 

One speaker has a tiny little chip, less than 1/16" and on the bottom back corner. The other has a pretty big chip, about 1" x 1/2" but thankfully on the bottom back edge. Filled both with JB WoodWeld, tinted with Mixol 22. I'll give that a couple of days before filing it down then will clean the cabs with lacquer thinner and apply some Watco Oil.

Still undecided about the grilles. They're a little dingy looking because they're beige and half a century old. One has a small stain that looks like rust. Spot remover and Oxy failed to remove that.

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Hi Kent,

Not sure if this will be helpful, but...

A while back I restored a pair of Seventeens with the same grille cloth.  One of my grilles also had a small stain that resembled rust.  Like you, I also tried to clean it to no avail.  Turns out the stain was isolated to just one horizontal thread of the fabric.  Eventually that portion of the thread disintegrated into powder.  I really don’t believe it was a conventional stain caused by a spill.  Instead, I believe something in this weave is subject to oxidation and eventual disintegration.  I ended up pulling a stray thread from the back of the grille and threading in to replace that missing portion.  Not perfect, but worked pretty well.  

 

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Thanks Tom

I checked and am pretty sure it's a stain, like rust. Still undecided on re-covering.

Meanwhile I started to clean a cabinet with lacquer thinner and it seems to be removing a finish. I thought these were just oiled but maybe not. Or maybe the oil changes over the decades. In any case, the original finish looks dull and muddy. I plan to strip them down to bare wood and see how they look.

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Untouched speaker on the left, stripped on the right.

After sanding down the epoxy repair I cleaned off the old finish with lacquer thinner, paper towels and #1 steel wool. It took off a lot of dark brown stuff. Then applied mahogany Howard Restor-a-Finish with #0000 steel wool. I'll finish up with clear Watco oil in a couple of days but here's a shot of an untouched cabinet and one after the cleaning and R-a-F. I've had even more dramatic results with Model Fives and Thirty-Threes.

So for anyone restoring KLH speakers, I recommend removing the original finish.

KLH_17_2 copy.jpg

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Hey Kent, those are looking really great - - I love restoration projects that are pulled from the trash heap! In your third post, is the thing you call the "shoulder washer" also made of rubber? - - it looks pretty thick in your pics. Also, about the finish - - do we know if the original KLH finish was an oil substance or something different? I know I've seen an original company document here about boiled linseed oil, but I cannot recall if that was for AR or KLH products (or both?).

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Hey Robert. Thank you.

Here's a stock pic of a shoulder washer to show it more clearly. The ones used with KLH speakers are black rubber and when used in conjunction with a rubber flat washer it isolates the machine screw from the metal plate. The smaller part of the shoulder washer is the thickness and diameter of the hole in the metal.

As for the finish, I dunno. The Seventeen brochure just says "genuine, furniture-grade walnut veneers" but no mention of the finish. I'm pretty sure it was AR that mentioned boiled linseed oil and recommended re-oiling periodically.

The Model Fives have a hard finish. It's not lacquer (like the Model Eight radio) and is a dog to remove. Varnish maybe. The finish on the Seventeens was not hard and shiny and it came off pretty easily with lacquer thinner. Maybe oil and a half-century's worth of grime? Again--I dunno. But these speakers were in very nice condition and aside from an unfortunate large chip in the veneer on the bottom of one, the cabinets were nearly pristine. But they were lifeless and dull. stripping the crud off revealed some nice grain.

I put a coat of Watco Oil on them this evening and I think they look pretty great. More pictures to follow.

-Kent

shoulder washer.jpg

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12 hours ago, JKent said:

...pic of a shoulder washer...

Yeah, that's a very good pic -- thanks -- now I can totally understand how that screw becomes fully isolated from the back plate, and yes, I agree that using conductive metal for the back plate might not have been the best decision. On so many other vintage speakers,  hardboard (Masonite) seems to work just fine for this purpose and does not present this problem of electrical conductivity, which then requires the special washers.  

12 hours ago, JKent said:

The Model Fives have a hard finish. It's not lacquer ... and is a dog to remove

And thanks again, this is good to know. The Fives are the speakers I had in mind - - I am several months late getting to a restoration of KLH Fives and every time I handle the cabinets I get to thinking about the finish. On this pair, the cab finish is pretty good but could be better, and I'm mostly inclined not to attack them with any vigorous re-finishing attempts.

Looking forward to seeing your completed project.

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1 hour ago, ra.ra said:

I'm mostly inclined not to attack them with any vigorous re-finishing attempts.

Veering a bit OT but the difference can be dramatic. This site had some great photos but now they seem all blurry https://pinkfishmedia.net/forum/threads/restoring-klh-5-speakers.90209/

I don't have before/after shots of my Fives but here are the Thirty-Threes. Old finish was "muddy". New looks great IMHO.

KLH33 after.JPG

KLH33 before.JPG

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On 10/10/2019 at 4:52 PM, JKent said:

These have impressive bass but the HF seems to be MIA.

Correction. I had the tweeter level switches in the center, which I didn't realize was the "Decrease" position. Switched them "Increase" and they now sound great. They do seem to like a lot of amp power. They came alive with the Adcom 555/II.

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Finished. That stubborn rust (?) spot finally came out by using a Q-Tip soaked in bleach.

They will find a new home in my niece's mid-century modern decor.

KLH 17 After 4 copy.jpg

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Yes, I have tried sanding but veneer is unforgiving and orbital sanders work fast. Sanding by hand with a sanding block should work.

The old veneers are thicker than new veneer but even so.......

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  • 2 months later...

Just discovered this thread.

Kent, you mentioned sealing the dust caps as well as the surrounds. That's the first time I ever heard about coating the dust caps with anything to help make the cabinets airtight. Can you elaborate on that a bit? I've used the sealing dope on the cloth surrounds, but never anything on dust caps.

BTW. Just to chime in on reworking the wood cabinets. I recently restored a set of KLH Model 22A speakers. I did a light sanding on the cabinets, then applied a coat of Watco Rejuvenating Oil, followed by a couple of coats of Butcher's paste wax, and was very pleased with the result. The finished product looked better than anything else I've tried with with restored speaker cabinets. For now, I don't know if it's because of the factory Model 22A finish, and I don't know if that will work with other KLH cabinets. I do know it looks better than the Tung Oil finish I used on my Model 6 restoration. Stay tuned.

 

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Norman,

If you go to the CSP library you will find 2 KLH Service Bulletins. One of them says to dope the “skiver” and dust cap on all speakers returned for service

Kent

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  • 2 weeks later...

Thanks for the info, Kent!

As it turns out I may be reading your initial post more carefully because I just got my hands on a pair of Model 17's late last week. The drivers are fine but the cabinets are in rough shape. I'm going to have to refinish them completely, including removing the previous finish along with some sanding, staining and sealing. The grilles are also shot, with the fabric torn on both speakers.The caps are on order from Parts Express. Your post about the correct sequencing on assembling the binding post was very useful. It explains why I had some trouble with one of the Model 6's I restored some months ago. (Yeah, what was Henry thinking on using metal back plates along with metal binding posts...) As soon as I put the finishing touches on the pair of EPI M100W speakers I have been working on, I can start the Model 17 restoration project.

I used to own a set of Model 20's from 1971 to 1985. They were my primary speakers during that period of time. It should be interesting to hear how the 17's compare. Unfortunately, I will be relying on a flawed sonic memory, along with my reduced hearing ability today, compared to when I was in my 20's. 

 

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A comparison would be interesting. As you probably know, the 17 and 20 were exactly alike except the 20's woofer was 4 ohm and the 17 was 8 ohm. That should make them sound a bit different. I assume the amp in the 20 (the speakers were part of a compact system) was tweaked to compensate for that.

I've owned 17s and 20s, but not at the same time and both are long gone. On my 20s I added a terminal cup from PE. The RCA jack can either be removed, bypassed or kept in parallel with the new terminals but if the jack is kept you should cap it with a rubber cap (I think 3/8" is correct), available in hardware stores: https://www.lowes.com/pd/Hillman-3-8-in-x-1-2-in-Green-Plastic-Screw-Protector/3012673?cm_mmc=shp-_-c-_-prd-_-hdw-_-google-_-lia-_-126-_-fasteners-_-3012673-_-0&store_code=1976&placeholder=null&gclid=CjwKCAiA6bvwBRBbEiwAUER6JRGcANyEk1nsZAo2t0brsAcbHWQftHOSygxDl8D9RIMZKHsS1IMmfRoCZHgQAvD_BwE&gclsrc=aw.ds

front_backcopy.jpg

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  • 2 weeks later...

I'm almost finished restoring the first KLH Model 17 speaker. Hand sanded the cabinets. Changed the capacitors and reinstalled the drivers. Put the first coat of slightly thinned tung oil on the cabinets and once it was rubbed in and dry I had my first listen. I did a side-by-side comparison with a set of both Original Large and New Large Advents and thought the Model 17 more than held it's own. As a matter of fact I think I prefered the Model 17 to the Advents. It's only a single listen on one amplifier (Harman Kardon HK 3490) in a basement room with less that ideal acoustics, but nevertheless the Model 17 was impressive.

I'll post some photos of the unrestored speaker and the restored one next to each other very soon. And I will also post when the 2nd speaker is completed with more listening comparisons to some recently restored KLH Model 6's, Model 22A's, and EPI 100 speakers that I own, along with how they sound when paired to my Fisher and Sherwood tube receivers.

One other thing. I narrowly lost out on a set of AR3a's at an estate sale in Clifton, NJ yesterday. They sold for $100 for the pair with a receiver thrown in the bargain. I was there when they opened the doors to the sale but another dude beat me to the basement where the speakers were located. The 3a's looked a little scratched and threadbare, but who cares for $100! Oh well, my search continues for a cheap set of AR classic speakers...

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