Diagnosing JansZen Jan-Kit 41: Help Needed!

Johnny_Law

Johnny_Law

o.O
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Hopefully some resident JansZen gurus are still posting here ... I need some help.

I recently acquired a set of 4 Jan-Kit 41s, each having a pair of e-stat panels with a 10" woofer each - I believe the same components were sold in cabinets as the Z-600. The previous owner of the seller's home installed the kits in custom in-wall redwood boxes. After purchasing the home, the seller remodeled the interior, pulled the speakers, and sold them to me, saying they did work and hoping I'd restore them.

The good news is that all of the kits look as if they've been in a time capsule for 60 years. The panels look great from the front and brand new from the back.

The bad news - I tested each - the woofers all work, but none of the e-stat panels power up or produce any sound. Each power supply is the same: 1000v across the wires coming out of one transformer, but 0v across the other transformer (I think - not 100% sure how to test a transformer). The bad transformer of each's power supply is the one labeled 5TA1 in the pic below.

In any event, the schematic is fairly simple, so I'm hoping someone can both educate me about how a transformer works, and specifically how to diagnose these kits to figure out what isn't working!

THANK YOU in advance. :music:

Here they are in the car home from the seller:

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Waiting to be tested with one of those SX-680s:

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Each is SUPER clean - seriously, like a time capsule :banana:

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And behind the panel (this one didn't have a fuse):

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Looks brand new :smoke:

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Resources I've managed to find thus far:

https://patents.google.com/patent/US2631196A/en

http://www.janszenloudspeaker.com/vintage DIY repair.htm

http://www.janszenloudspeaker.com/vintage.htm

ztatic said:
For those who are willing to try stuff for themselves: First make sure the AC line step up transformer is working. It's the conventional looking unit connected to the AC. I think the secondary voltage should be in the 600VAC range, which gets approximately doubled by the voltage multiplier to supply the membrane bias of about 1100VDC. Sometimes the secondary opens up. Sometimes the secondary has shorted windings. Next, the multipliers in the older units used selenium rectifiers, which are not long lived. Replace with plain old 1N4007, and you may be back in business. Another weak element in the older units would be oil/paper caps in the same circuit, which crack open eventually. Replace them with HV ceramics: .047uF/1kV ought to do it. There's also an electrolytic in the crossover that is supposed to be kept under bias at all times, but if the circuit doesn't allow for this, or the unit hasn't been plugged in for a long time, it may have failed. If you're handy with a screwdriver and soldering iron, all that is so cheap and easy, it should come before trying to diagnose or fix problems with the tweeters or signal step up transformers.
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(I'm just not completely sure how to test these things ... and namely how to figure out if my e-stats are bad!)
 
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Assuming you've already plugged them in without smoke while testing, you might try leaving one on for a day or two. My black pair of Quad ESLs takes about 5 days to get the tweeter panels charged up fully - probably indicative of leakage paths. Don't apply much of a music signal until they've had a long time plugged in. Maybe disconnect a woofer temporarily to hear the tweeter better? Does the "failing" transformer have any connection to the AC? If not it won't have voltage without a music or test signal, but don't apply those until they've had charge-up time.

A transformer works by converting electrical energy to energy in a magnetic field, and back again. Windings create the magnetic fields, and the ratio of primary turns to secondary turns of wire provides a proportional voltage step-up, or step-down.

I would think the selenium rectifiers and caps would be more likely culprits than the music signal transformer if you still don't have sound.

OTOH, someone with more knowledge may advise on a specific testing procedure.
 
Thanks a lot for the help. In the interim I've been busy with some AR-4x's but have been looking forward to getting these going.

So yesterday I picked one of my four to use as my test subject. I replaced its selenium rectifier with a string of three 1N4007 (or ~equivalent) diodes from Radio Shack. Now, when I plug the unit in, I can hear a faint static coming from the panels, but they still do not produce any sound when connected.

One potential issue, when my ear was up to one panel listening for noise, I think a stray hair landed on a panel, and one string looks to have instantly snapped with a little pop. I hope this didn't kill the entire panel.

So now I have the panel plugged in and will try again every day. Will also try to diagnose the original capacitor and step-up transformers.
 
Wow, what a great find and project! I know you won't give up and will persevere, but it must be tough with this thread languishing a bit. Have you made any headway? Did you leave a pair plugged in for a week, then try?

Have you pondered the situation on The Tree of Woe?

Biggles

ps - I've owned approximately 36 vehicles since I was 16. I can say with authority that none of them had an engine with those wheelie macog action deals.
 
Oh hey! How slow can you progress with it still called "perseverance?"

Today I finally took another step - I ordered a single 20uF Dayton (along with a fresh batch of caps for some Polk Monitor 7s I picked up!), and when the cap gets in, I'll replace the original in this one test crossover. I have a hunch that one of the transformers is bad but KNOCK ON WOOD I hope not!
 
How slow of progress can still be considered progress? Pretty slow. As long as you still have the project, you're good to go!

Keep at it, keep pushing forward. One step at a time.

Biggles
 
You rule! I just knew if you stuck with it you'd get those suckers back up and going. Congratulations! It's going to be a lot of fun hunting for just the right cabinets with a high cool factor. I'm jealous.

Biggles
 
Heck yeah! I wish I could find something as nice as these Barzilay cabs that I randomly just found on the auction site: http://www.ebay.com/itm/Vintage-Jan...-in-Barzilay-Cabinets-Rare-Nice-/291600747465

Going to see if I can experiment with cardboard boxes in the garage to find an ideal cab volume. Interestingly, looks like JansZen (Neshaminy) recommended 2 ft3, from a quote I found in Jan. 1961 High Fidelity magazine (although the quote cites the Z-400 components although I thought it used the Z-600 components :dunno:):

https://archive.org/stream/rm_High-Fidelity-1961-Jan/High-Fidelity-1961-Jan_djvu.txt

"Baffle It Yourself. On a recent trek into Pennsylvania we found the Neshaminy Electronic Corporation readying a kit version of their Z-400 speaker system (the Model 350 woofer used in conjunction with the two-element JansZen electrostatic). Called the Jan Kit 41. it is no kit in the usual sense of the word. Actually, it is the Z-400, minus enclosure. The speakers are mounted on a half-in.-thick panel, fully wired, ready for whatever kind of installation the purchaser wants (in separate enclosure, behind a wall, in a rigid component cabinet, or wherever). Only two cubic feet of enclosure are needed. The firm says that any increase beyond this size does not drastically increase the efficiency or reduce the resonant frequency of the speaker in the enclosure. Going from two to three cubic feet adds only 1 db of bass efficiency below the two-cubic-foot resonance frequency. The slight gain, says the firm's Phil Klein, is more than offset by the increase in cabinet volume and cost. And speaking of costs, the purchase of the Jan Kit 41 at $99.95 represents a saving of about $35 for the person who doesn't need the Z-400's enclosure."
 
Bringing my own thread back from the dead ... I still have not gotten two of the tweeter units working, but two of them are. All four woofers make noise, unfortunately one of them suffered some cone punctures during a recent move, I will patch it up. Also I believe the accordion surrounds at one point were damped with something, which has since dried up. Luckily I still have some AR damping fluid around so I may try it out.

In the meantime, I realized that the black panels come apart, so now I have four individual tweeter panel boxes and four 10" Janszen 350B Alnico woofers. It seems like an elegant solution would be to put each woofer in a properly sized box, and sit the tweeter boxes on top. I am wondering whether I should find large boxes, and run two woofers in each box, or smaller boxes, one woofer per. Or a larger box where each woofer gets its own chamber (like a McIntosh ML-2C or Infinity RSII).

Does anyone know what the T/S parameters are for these woofers? I emailed Janszen directly and got no response. If not T/S parameters, any suggestions on box size?
 
I don't think its going to fit in the cabinet..

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avionic said:
I don't think its going to fit in the cabinet..
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Dang, good point. I wish I'd measured those in-wall cabinets before I tossed them.

I could get there by figuring out the volume of Z-600 cabinets and subtract the volume of the tweeter panel boxes. Z-600s come up from time to time ... I've tried to ask about the dimensions but not gotten an answer.

Page 10 of High Fidelity Dec 1968 shows an advert w/ the Z-600 and Z-41 mentioning cabinet construction advice would be given if asked for. I wonder if @ztatic might respond to this Bat-signal. :p

Actually, bingo, found reference to what a double-woofer box might look like, apparently 5 cubic feet; implication is that a single-woofer box should be 2.5 cubic feet: "Neshaminy has announced what in effect will be a "double Model Z -600" speaker system. The five -cubic -foot enclosure will contain two woofers and four JansZen electrostatic tweeters, for about $395." See High-Fidelity October 1966 page 74.

Better yet, flipping to page 159, the dimensions of the Z-600 are noted at 26 5/8" h x 20" w x 13" d. If we assume the inner dimensions are ~1.5" smaller, this gives an internal volume of ~3 cubic feet. Now we remove the volume of the tweeter panel box (~0.3 cubic feet), we arrive at ~2.75 cubic feet of volume. Woo, corroboration (well close enough)!

So I guess that's that. I've never built my own speaker box before, this could be fun.
 
I dunno. Dragged em home, there they sit. Iam hoping to toss them into a guests vehicle when theyre not lookin. Ive got a lot of those items around here.

Biggles
 
drbiggles said:
I dunno. Dragged em home, there they sit. Iam hoping to toss them into a guests vehicle when theyre not lookin. Ive got a lot of those items around here.

Biggles
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Ha! You know, if they do work, those e-stat panels might be nice on top of a Bozak?
 
Johnny_Law said:
Ha! You know, if they do work, those e-stat panels might be nice on top of a Bozak?
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Yup! Considered parting them out. At first glance, the woofers look unremarkable. Even so, iam having a hard time breaking them up. Id rather pass them along to someone who's interested.

Biggles
 
drbiggles said:
Yup! Considered parting them out. At first glance, the woofers look unremarkable. Even so, iam having a hard time breaking them up. Id rather pass them along to someone who's interested.

Biggles
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:smoke: What about a certain mutual friend of ours, last time I checked he was going through speakers like a mad man, Vandersteen, JBL, Infinity ...
 
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