Quickie: KLH Nineteens

[JKent]

KLH had a practice of re-packaging the same speakers with different names. The Model Nineteen speaker was part of the Model Nineteen compact stereo system (which, btw, had a very nice dust cover for the record player/amp). The speakers are nearly identical to the Model 14B and Model Fifteen: Two of their great 4" drivers in a PORTED 14" x 8" x 8" cabinet. The drivers are wired in parallel internally and there is no filter or crossover--that was handled by the amplifier circuitry. Connection is made via RCA jacks. Speakers that were NOT part of a compact stereo system such as the 14, 14B, 15 708 and other DID have an LCR electronic filter and were equipped with screw terminals.

I've had these in the past and they are exceptional little speakers, given their size and simplicity. The current pair was picked up at the 2017 Kutztown radio show and they were in decent shape. One had some dings that I filled with brown epoxy, and the grilles were a little tired looking.

So the refurb consisted of refinishing the cabinets (light sanding, Howard RAF and Watco Danish Oil), replacing the grille cloth and adding some felt feet.

Interestingly (to KLH geeks) the 2 speakers had different construction: Speaker 1 was sealed and had a removable grille attached with Velcro tabs Speaker 2 had a removable back held in place with 4 wood screws. That panel had foam around the perimeter (deteriorated, so I replaced it). Inside there were wooden blocks that held the front baffle in place. Sandwiched between the baffle and the cabinet frame was the grille: cloth glued to thick cardboard.

Speaker 1's grille was Masonite. I removed the stapled-on cloth, sanded the Masonite to remove dimples from the staples, sprayed with lacquer to seal the surface and prevent future "bleed through" staining then attached a piece of Charles Craft Irish Linen using Aleene's Tacky Glue on the back of the Masonite. The Velcro patches were re-attached with epoxy and clamps. After all the glue was dry I spritzed the front of the grille with water and dried with a hair drier to shrink it so it was nice and taut. I then sprayed it with Scotch Guard. Finally, although the speakers did not originally have KLH badges on the grilles I applied one of my reproduction small badges.

Speaker 2's grille was restored similarly. The cloth had been glued to the face of the cardboard and when it was peeled off the surface was rough and green (??!). So I flipped it over, used some wipe-on poly to soak in and seal the surface, then re-covered it just like Speaker 1 but without the Velcro.

These put out a lot of sound from a small box. They weigh an impressive 12 pounds each. The 4" driver (which KLH called the "Twelve point five" driver) was first used in later Model Eight radios, then in all 5 versions of the Twenty-One radio. It was used as a single driver in the Model 11 suitcase stereo. It was also used as a single driver in the Model Twenty-One extension speaker and that speaker appeared in other models such as the 11w. It also appeared as the Model 708, which had a filter network and screw terminals. Dual 4" drivers were used in the 14, 14B,  and 15. The top-of-the-line KLH Model Five and its big brother the Model Twelve both used dual 4" drivers as their mids. A single Nineteen makes an excellent extension speaker for a KLH radio and sounds better than the standard extension speaker because it has twice the volume and the port gives it a fuller sound. The Twelve Point Five driver has been compared to the Foster FE-103. It's a very worthy driver.

[ra.ra]

That's a great effort, Kent - - those li'l fellas look terrific. I love all of these small speakers with that 'classic' look, and these have such wonderful proportions. And, good call with the application of badges - - not only do they look better this way (like the Fourteen B and Fifteens).... but hey, it's not like you had to go shopping around for some badges!  These would look great and integrate well on some office shelves, above kitchen cabinets, or for a small bedroom system.

After looking back on some threads for the Fourteen B, I've become real curious about the filter components used in that model. Is it your understanding that - - unlike the Nineteen and Fifteen - - the two drivers in the Fourteen B are responding to different frequency ranges?   

 

 

[JKent]

On 6/26/2018 at 10:23 AM, ra.ra said:

Is it your understanding that - - unlike the Nineteen and Fifteen - - the two drivers in the Fourteen B are responding to different frequency ranges?   

No. I'm no expert on filters so maybe someone else can chime in but single-driver designs typically have filters to shape the response curve. Below is a photo of the LCR filter from a KLH Model 708 (the 708 is identical to the 21 extension speaker or the 11W speaker except for the screw terminals and this filter). Also have a look at Zaph. The 2nd photo is a Zaph design single-driver speaker I built. As you can see, it has a pretty sophisticated filter network. Here are the plans: http://www.zaphaudio.com/audio-speaker18.html

btw--this is off on a tangent but the single-driver project was a lot of fun! I have a friend who works in a stair-building shop and he gave me cut-off pieces of an oak newel post. I asked him for some solid oak to make end pieces and built the little satellites shown. They're smaller than Zaph's specs but this is what I had available to work with. 

Then I found a nice Celestion subwoofer at Goodwill. It worked but one of the front covers was missing so I asked my friend for 2 more pieces of oak, which he cut to size and even made the front curve like the original plastic.

The sub/sat went to the friend's son so I then built another sub/sat, this time with a Polk sub from GW and maple sats to give to his other son. 

And thanks for the kind words Robert.

 

 

 

[alkermes]

I wonder how one of the 19's would sound connect to a Model 21 radio.

[JKent]

1 hour ago, alkermes said:

I wonder how one of the 19's would sound connect to a Model 21 radio.

Great!