KLH Model 20 Plus Grill Badge Placement?

[Joe Nardy]

I'm working on a KLH Model 20 Plus system for @RDSChicago (check out some pics of this system if you'vre never seen one. It's a very cool mid-century modern system). His speakers originally had a KLH badge on the lower right of just the right speaker. He found some replacement badges on the auction site but I'm not sure where they're supposed to be placed on the speakers. I've seen pics with the badges on the outside of the left and right speakers, pics with both badges on the lower right of both speakers, and pics with just one badge on the lower right of just the right speaker. I found a pic of a brochure or ad for the 20 Plus on Classic Speaker Pages which doesn't appear to have a badge on the left speaker but the lower right of the right speaker is hidden behind a chair.

Does anyone know the correct number of badges and placement?

Thanks,
Joe

 

[marcthisdate]

If it helps I found this.. Look at the below image of the unit in the operating instructions. Badges are shown on the speakers right side corner.

 

[Joe Nardy]

If it helps I found this.. Look at the below image of the unit in the operating instructions. Badges are shown on the speakers right side corner.

Marc,

Yes, this clears it up. That's the first official document I've seen that shows the badges. Do you have the printed operating instructions? If so, would it be possible to get a scanned copy?

Thanks,
Joe

 

[marcthisdate]

Joe, no I don't (photo was grabbed from the internet) but I did find this on HiFi Engines site... https://www.hifiengine.com/manual_library/klh/twenty.shtml
You will need to create an account to download but at least its free.

 

[ra.ra]

Numerous online images show a variety of badge placements (including no badges!) that all look good, but I suspect the lower right corner is the "official" designation. Nonetheless, the more interesting question is do you place the tweeters inboard or outboard?

 

[Joe Nardy]

Numerous online images show a variety of badge placements (including no badges!) that all look good, but I suspect the lower right corner is the "official" designation. Nonetheless, the more interesting question is do you place the tweeters inboard or outboard?

I'm pretty sure I can answer this one. I believe the tweeters should be placed outboard. On the system I'm working on both speaker cabinets have the same serial number followed by "L" and "R". I think it's fair to assume those represent left and right. With the cabinets placed according to the "L" and "R" designations (looking from the front) the tweeters are outboard.

Thanks,
Joe

 

[ra.ra]

...the tweeters are outboard...

That is how I always place my speakers when in horizontal orientation, but it's interesting to know about the "L" and "R" designations established by Dynaco on the factory labels.

 

[Joe Nardy]

Here's the Model 20 Plus System I've been working on....



This was in pretty good cosmetic condition when I started working on it. The cabinets were treated with Howard Restor-A-Finish (0000 steel wool) and Feed-N-Wax. Stands were stripped and re-painted with gloss white paint. Crossovers were recapped with Dayton Audio Poly caps. Woofer surrounds were resealed with the proper sealant. Driver baskets were sealed with Parts Express speaker gasket tape, along with duct sealer along the thin straight sides of the woofer baskets. The hood hinge mechanism wasn't assembled as designed so the spring would not hold the cover open. The hinge pivot point rivets and holes were worn so there was a lot of play in the mechanism. When I put it together correctly the play caused the mechanism to scrape the inside of the cabinet. I cut a piece of clear Lexan and installed it under the side mount point of the hinge mechanism so it now contacts the Lexan and won't damage the finish of the cabinet. I installed a new power cord and (much) heavier speaker wires. I made new grill frames from thicker 1/4 inch Masonite and replaced the grill cloth with Onlinefabricstore Ivory Polyester Linen. Badges are reproduction from the auction site. They look good but are a bit larger than the originals and are printed or screened so they don't have the raised letters and border like the originals. The owner saw it yesterday and was very pleased with the results.

Thanks,
Joe

 

[ra.ra]

Beauteous.....thx for sharing.

Not sure if you've been inside the speaker cabinets yet, but one thing I'd like to see confirmed or disputed. These cabinets are so much deeper than the regular KLH Twenty: is there an intermediate panel in these cabinets (and therefore a void in the rear) to give these Twenty Plus cabs identical internal volume to the Twenty cabinets?

 

[Joe Nardy]

Beauteous.....thx for sharing.

Yes, this is a very nice example of the Model 20 Plus. Unfortunately, it isn't mine :-(

Not sure if you've been inside the speaker cabinets yet, but one thing I'd like to see confirmed or disputed. These cabinets are so much deeper than the regular KLH Twenty: is there an intermediate panel in these cabinets (and therefore a void in the rear) to give these Twenty Plus cabs identical internal volume to the Twenty cabinets?

Yes, I was inside the speaker cabinets (recap crossovers, reseal drivers and woofer surrounds). There were no intermediate panels inside the cabinets. I'm not sure how the internal volume works out between the Model 20 and Model 20 Plus. While the 20 Plus cabinets are deeper, they aren't as wide (or tall since they are oriented sideways). I've never seen a regular Model 20 in person but looking at pictures you can see that the Model 20 cabinet is wide enough that the woofer baskets are fully round. On the 20 Plus the woofer baskets are cut straight on the sides (which makes them somewhat difficult to seal) so, assuming the woofers are the same diameter, the cabinet is smaller in that dimension. Without knowing exact dimensions it's hard to determine how much difference there is in internal volume between the two models. For comparison, the Model 20 Plus speaker external dimensions are 19 in. X 15 in. X 10 5/8 in. If anyone can provide dimensions for a Model 20 we should be able to get a good idea of how the internal volumes compare.

Thanks,
Joe

 

[RxDx]

hwih: 9" x 23.13" x 11.75" = ~2446 cu in = ~1.4 cu ft
19 x 15 x 10.63 = ~3029 cu in = ~1.75 cu ft

Always wanted to compare a 20+ speaker system. Always got ambushed
on the way by 12" AR systems ;-)

 

[RTally]

My Model Twenty speakers measure 23-1/8” x 11-3/4” x 9” D deep. According to this page, the same as Model Seventeen.

I assume your speakers are 15" deep since your woofer has flat sides.

Edit: RxDx beat me to it by a minute.

 

[ra.ra]

hwih: 9" x 23.13" x 11.75" = ~2446 cu in = ~1.4 cu ft
19 x 15 x 10.63 = ~3029 cu in = ~1.75 cu ft

If these are external cabinet dimensions, they do not necessarily correlate with any comparison of interior volume. Post #10 astutely notes that the Twenty Plus woofers have their baskets clipped to fit the 20+ cabinet dimension, but are we certain that otherwise this woofer is identical to the Twenty woofer? If so, it might make sense that they were fitted to perform with similar interior cabinet volumes, yes?

The only way to debunk this notion of an intermediate cabinet panel (to limit and define interior volume) is to stick a tape measure inside the 20+ cabinet and compare it to the exterior depth dimension. I may be wrong, but this pic suggests to me that the interior depth dimension may be far less than the external depth dimension.

 

[Joe Nardy]

If these are external cabinet dimensions, they do not necessarily correlate with any comparison of interior volume. Post #10 astutely notes that the Twenty Plus woofers have their baskets clipped to fit the 20+ cabinet dimension, but are we certain that otherwise this woofer is identical to the Twenty woofer? If so, it might make sense that they were fitted to perform with similar interior cabinet volumes, yes?

The only way to debunk this notion of an intermediate cabinet panel (to limit and define interior volume) is to stick a tape measure inside the 20+ cabinet and compare it to the exterior depth dimension. I may be wrong, but this pic suggests to me that the interior depth dimension may be far less than the external depth dimension.

I'm not sure whether the woofers are identical or not. However, I think the pic provides a clue that there is no intermediate panel. You can see the terminal/crossover panel in the pic and also see that it extends to whatever the rear panel is. Looking at the bottom of the speaker cabinet, the opening for the terminal/crossover panel is less than one inch from the external rear panel of the cabinet. The terminal/crossover panel extends beyond the opening roughly 3/8 inch to allow for mounting and sealing. I had these out to recap the crossovers and used Parts Express speaker gasket tape (3/8 inches wide) to seal the terminal/crossover panels. That leaves less than 5/8 inch to account for the thickness of the rear panel. I think it's safe to say that the panel shown in the pic is the rear speaker panel, not an intermediate panel. Had I known this conversation was coming while I had the cabinets open I would have gladly taken some measurements but I'm not curious enough to re-open one to confirm or deny. Maybe someone will chime in who has access to an open cabinet.

Thanks,
Joe

 

[ra.ra]

I think it's safe to say that the panel shown in the pic is the rear speaker panel...

You're in a better position to confirm this than I am, but I've never seen this issue fully explained regarding the differences between KLH-20 vs. 20+ cabinet dimensions and interior volume.
Nonetheless, it's a great system and truly one of the best-looking products from that era.

 

[Joe Nardy]

Yeah,

I wish I had known there was so much curiosity about the differences between these two speakers. I could have taken all the measurements to help clean up the issue.

Thanks,
Joe

 

[RxDx]

Probably the least-documented of the early KLHs, with the possible exception
of the Model Twenty Eight.

 

[ra.ra]

Model Twenty Eight.

The Twenty-Eight is a very interesting speaker model. There is a terrific restoration thread here on AK, but unfortch, the wonderful and comprehensive pics are no longer viewable.