• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

KLH 17's masquerading as 6's?

T

Trygve

New Member
I have a pair of speakers I got from my grandparents. As far as I know they purchased them new in the early '80s. On the back they claim to be KLH Model 6's:

PXL_20210603_172918959.jpg

I did some reading around here and got pretty excited, as those have a great reputation. They don't sound awesome though - voices are indistinct and fuzzy. I think this means I should replace the capacitors? I have some electronics experience, so I'm comfortable with that.

Thing is, from the inside these speakers look to be Model 17's. There's a "KLH 17" stamp underneath the grill (just to the right of the tweeter):

PXL_20210522_143845137.jpg

and the crossover looks like it matches schematics of 17's I've seen posted:

PXL_20210603_130410548.jpg

PXL_20210603_130935635.jpg

Any thoughts on what these really are? Are they worth going through the trouble of ordering and replacing capacitors? Thanks for any insights!

(This is related to another post of mine: https://audiokarma.org/forums/index.php?threads/putting-together-my-first-system.960758/. That one's more general, about my overall system. Hope it's ok to break out this specific speaker question!)
 
Register to hide this ad
Trygve said:
I have a pair of speakers I got from my grandparents. As far as I know they purchased them new in the early '80s.
Click to expand...
I don't have much to offer, except the fact that the classic KLH line (5, 6,17, etc) was long out of production by the 1980s. As far as I've been able to tell, its last year of manufacture was 1975.
 
Those are certainly not Seventeen cabinets, they have a characteristic raised front trim. Your front edges are flat. Also, the Six has an offset from center tweeter as yours do. Seventeen layout is oriented vertically or very nearly so.

I believe you have a real nice pair of Sixes, a true classic. Although the Seventeens ain't no slouches, either. Congrats. And yes, recap them, redope the woofer surrounds, and prepare yourself for listening bliss!
 
Last edited:
Those are Model Six speakers.

There are several differences between the Model Six and Seventeen.

1. The Six has an inductor in the woofer crossover circuit. That inductor is shown attached to the inside of the back panel.
2. Dimensions: see http://www.aphenos.net/electronics/speakers/klh/all_klh.htm (the 17 is slightly smaller)
3. The 17 cabinet has a square protrusion surrounding the grill, whereas the 6 has a flat front surface.
4. Driver size: the Six has a 12" woofer and the Seventeen has a 10" woofer

plus the reasons illustrated by Dswankey and alteclipsch
 
Trygve said:
(This is related to another post of mine: https://audiokarma.org/forums/index.php?threads/putting-together-my-first-system.960758/. That one's more general, about my overall system.
Click to expand...

If you're wondering why you got no responses to that initial thread and would like to get some feedback hit the "Report" button in lower left corner of that post and ask a moderator to have it moved to "General Audio Discussion" you posted to a sub-forum that doesn't see that much traffic
 
It's got the inductor inside. The Sixes have the inductor. The 17's do not.

Agree with the others. They are Sixes.
 
Yep, looks like the last generation Model Six with vinyl clad cabinets. The 17 is just an inspectors stamp, these often cause all kinds of confusion when they are spotted on KLH speakers because people think they are referring to the KLH speaker of the same model if there is one. Re-cap and enjoy them!
 
I had the impression the little KLH stamp on the front panel was likely some final inspection on the line, they then stamped it. Figured each inspector had a stamp number. My 17s in the workroom were from consecutive days back in 1972 got stamp #9 and the 6s in the living room were consecutive serial numbers in 1971 got stamp #10. Both stamps have the same shape as yours.

The 17s had the line number and date stamped on the inside just below the crossover, the 6s on the front panel. In May 1971 they had passed 160k on the serial numbers with the 6.

Worth fixing. Appealing sound to these old speakers. The 17s are like the 6s but not as low on the bottom end. Same tweeter used in both.
 
Last edited:
dly66 said:
I had the impression the little KLH stamp on the front panel was likely some final inspection on the line, they then stamped it. Figured each inspector had a stamp number. My 17s in the workroom were from consecutive days back in 1972 got stamp #9 and the 6s in the living room were consecutive serial numbers in 1971 got stamp #10. Both stamps have the same shape as yours.

The 17s had the line number and date stamped on the inside just below the crossover, the 6s on the front panel. In May 1971 they had passed 160k on the serial numbers with the 6.

Worth fixing. Appealing sound to these old speakers. The 17s are like the 6s but not as low on the bottom end. Same tweet used in both.
Click to expand...

There are also some that have a stamp on the front baffle board that says STYxx with the two digits being the year built (every one with the STY stamp I have checked corresponds to the date stamped on the drivers). I think it depends on which factory built the cabinets for them just like the various stamps inside the classic AR speakers. I also have some KLH gear with M-12 stamped on the chassis that obviously has nothing to do with Model Twelve speakers (I’ve seen it on unrelated speaker drivers, a phono system, radio etc.) Maybe it’s the same assembly line that built Model Twelve parts, we’ll probably never know.
 
RTally said:
Those are Model Six speakers.
There are several differences between the Model Six and Seventeen...
4. Driver size: the Six has a 12" woofer and the Seventeen has a 10" woofer
Click to expand...

This "fact" has been corrected in previous threads. The Model Six has a 10-inch woofer. Here are the exact dimensions: cone radiating surface 9 1/4 inches across; outer edge of basket 10 3/4 inches across. The front baffle is only 11 1/16 inches wide, so a 12-inch woofer could not fit.
 
anytune said:
This "fact" has been corrected in previous threads. The Model Six has a 10-inch woofer. Here are the exact dimensions: cone radiating surface 9 1/4 inches across; outer edge of basket 10 3/4 inches across. The front baffle is only 11 1/16 inches wide, so a 12-inch woofer could not fit.
Click to expand...
I think the point RTally was making was that the Six has a much larger woofer than the Seventeen.
 
Sorry for the delayed reply! I missed the "You will not receive any further emails about this thread until you have read the new messages." in my email. Frustrating, that. Anyways, thanks for all the thoughtful replies! Very much appreciated. Consider me thoroughly convinced, and excited! Ordering caps and surround sealant kit today.

Regarding my confusion: looks like I didn't read quite enough! Crossover for 6's and 17's looks to be very similar. My sixes have the newer Temple capacitors, so they look different (smaller) than the big ones I've been seeing in photos of older sixes. Must have stumbled across a photo of newer 17s and thought: "Those look like mine!". The single "2+2" loudness cap also threw me, but looks like I can replace that with two separate 2uF caps.
 
Never met a Temple that worked. I've restored dozens of various KLH speakers and almost all of them had silent tweeters until I changed the Temples to new Daytons. A few had broken tinsel leads, most of them repairable. I'm about to do a pair of Twenty Fours as soon as the caps arrive.
 
Last edited:
Caps replaced and surrounds sealed! I need to figure out a couple more components of my system before I can test them properly, but early indications are good. I'm unsure whether I've sealed the surrounds properly though. I've read that when depressed, the woofer should return slowly. It returns more slowly than when not installed in the cabinet, but not by a lot. (See the video below.) Should I expect a slower return?

Testing seal on woofer surround

  • Media owner Trygve
  • Date added
 
Be sure the woofer gasket or compound is sealing the woofer to its mounting surface and there are no leaks around the screws (same with the tweeter). Some folks also look at the interior cabinet joints and the crossover edges. Any leaks contribute to poor seal.

The cone won't return slowly when out of the cabinet since it's the cabinet that provides the pressure changes.

Nice job on the application. I think you may be done, others will chime in. When you push the cone down, use even force straight down and hold it down for just a bit to equalize the pressure inside and out. Don't bottom it out.

Nice video, BTW!
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom