jessiAV

You are quite correct that high current amplifiers can drive lower impedance loads reasonably well. Reproducing dynamic music means that there will be short-duration current demands from your amplifier, which typically last much less than 1/4 of a second. However, a speaker's impedance/reactance characteristics remain largely predictable.

There is a screen covering Norman's tuned port, but otherwise the vent appears nearly identical to the Ten's.

For some reason, your pictures at gmail don't seem to open for me. Like your Thirty-Threes, the Ten's port is open. It's six inches deep and ends just about 1 1/2 inches from the rear panel. You tweeters may be repairable with very careful 'surgery'. I will try to write you via CSP's mail with details.

Photos taken as it was opened for the first time.

The precursor of the Model Thirty Three, Seventeen, Twenty and similar small KLH speakers? Made around 1960. Wood veneer cabinets, as was usual of course. The dampening within the cabinet is typical fiberglass, and it is filled up to about the height of the tweeters. Their original frames with typical KLH off-white grill cloth and black scrim were retained behind the wood surround trim, maybe as Velcro wasn't widely used in 1960?

Actually, it's just a confusing photo. Both speakers are identical, although the right one is fitted with a fiberboard frame for a yet-to-be-installed grill cloth. Sorry for unintentionally leading you astray with a lower-rez image. You are right, the cabinets are almost the same dimensions as the Seventeens (about 1/4 inch higher). Anyway, the woofer surrounds feel noticeably stiffer as compared to my 1965 Seventeens. I will start a new thread about these soon as there is too little information online. Norman, maybe let me know if you decide to sell the tweeters?

Norman, my Model 10's are also a ported design like your Thirty-threes, and have woofers that visually look identical to my Model Seventeens. Both measure about 8 ohms DCR as well, but pushing on the woofer cone is much easier on the Seventeens. Maybe Roy can give us more insights about these models? Here is a photo of the Model Tens:

Looking for a 'thick-plate' Tweeter (Seventeen, Six, etc). Anyone?

These tweeters are sold. Thank you.

Okay Roy. I've sent you an email.

As sixty dollars a pair (plus shipping) appears to be a typical purchase price for Advent 'egg' tweeters, I would sell these for that amount. I wasn't trying to be greedy, I just didn't find a similar-condition listing available when these were offered before.

The cabinets appear to have been painted, and even the front inside trim is painted white, instead of the correct black.

Scottie, what are you asking for your Five tweeters?

Ohm readings are 3.8 and 3.9. Asking $45 for one or $80 for both, plus actual shipping (Priority Mail Flat Rate box probably makes the most sense but whatever you prefer of course ). Thank you.

See the For Sale/Wanted section here at CSP.

Two available. One from 1972 and the other from 1973. jessi-pm@juno.com

Your research is correct, you have one late and one early Model Six, and yes, the front baffle w/grill on the early one will be quite(!) difficult to remove intact. This can sometimes be pushed out by removing the metal plate on the rear (with it's epoxied-in crossover capacitors) and pushing the front off from behind using this opening. To avoid causing any additional damage on my early Six, I choose to simply cut away the KLH cloth grill and then renew it over a new fiberboard grill frame . The failed capacitor that silenced my tweeter was mounted inside the front panel below and to the right of the tweeter. It was possible for me to reach this cap (barely) through the tweeter hole. The Six is a truly wonderful speaker, as you will discover after repairing it.

My feeling the Model Seventeen tweeter is one of the closest matches to a Five tweeter there is. The magnet on the 5's unit is located slightly closer to the basket than in the 17. While I have the Five, Six and Seventeen (and Ten) models it seems like they sound very similar, maybe the Fives are a little more 'crystalline' and the 6/17 tweeter a little more 'present', if that makes sense? Sorry for the belated reply. I almost never visit here now.

AFAIK, all Model Six's have the same crossover components. Certainly, my early (epoxy woofer) versions have the same parts as Brad listed (8-2-2uf caps + resistors & switch) earlier this thread and I've never read of any Six owner discovering different crossover component values in their unmodified speakers. It seems like the part that typically fails is the 8uf capacitor, the others, rarely.

Brad, I note that in your posted pictures your woofers have different dust caps (apparently original and black replacement). Maybe they are contributing to the difference in energy you are hearing?

Love the ARvid label! I'm surprised you changed your 18 count grill cloth, as nice as it looked.

So to update this thread, I will say I'm extremely pleased with my Fives at this time. While the quality of the bass is as excellent as expected from a Kloss design, the midrange's freedom from distortion is just remarkable. World class. Personally, I would like a bit more energy at the woofer/midrange crossover point, but that should come as I continue to work with the speakers. For now, I'm just enjoying my music and discovering newly revealed subtle details my modified OLA's couldn't achieve. BTW, these KLH woofers do have the cone weight written on the inside, the ink has just faded and so they are difficult to see. And with Roy C's majik sealant, they certainly go as deep as the OLA's. Finally, I just love the cabinet's front shaping and color of it's wood. Lovely stuff.

It sounds like this is a job for a professional. Without seeing it I can only guess of course, but maybe the 'bang' was one of the capacitors inside failing from old age? Repairing it should be quite straightforward for a qualified technician. The model 20 is a nice unit, and it's speakers are lovely sounding.

My test equipment is used in digital systems I encounter at work. Still, I also have a Mega 328 based (100k) tester that one other member here has used. Good for high frequency work, but as you accurately point out, not so much for audio frequencies. Not sure what to say about the E-Caps? If I try re-capping again, I may try some of my plastic caps (2 to 10uf values from Conrad Johnson, Kimber, some old Sideral, and Erse) tho it might be neat to fit something better. My second pair of OLA's were re-capped with Erse; which were pleasant but I wonder if there are nicer caps out there?

Good question Brad. Since the E-caps did not work well (too bright surprisingly) with my Five's crossover, I'd be very grateful to learn what would be a good cap in this application. Kent would be a great adviser if he was able to evaluate the crossovers he renews connected when to the speakers, but it seems he hasn't had that opportunity. As it's clear I am not a passive filter expert, I was wondering about the cap across my KLH's woofer. Of course it's part of the LC filter, but does it also help damp the back EMF of the woofer's coil (at resonance?) as well? If so, it would be a clever way of smoothing the woofer's response. 😀