Audiokarma.org
Audiokarma Featured Sponsor

Go Back   AudioKarma.org Home Audio Stereo Discussion Forums > Speakers


We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #1  
Old 09-03-2007, 08:17 PM
clydeselsor's Avatar
clydeselsor clydeselsor is offline
AK Subscriber
 
Join Date: Jul 2007
Location: N.W. Indiana
Posts: 10,683
Janszen Z-600 issues

I bought a pair of Janszen Z-600 speakers a few years ago at a thrift store for 20 bucks and they worked great. They have a 10" woofer and 2 electrostatic panels for the highs. I have used them off and on since I bought them but recently it seems that the high frequencies have dropped quite a bit. Could this be a power supply issue? If so, is the power supply a difficult rebuild? I have moderate experience recapping tube amps and stuff like that, but that is about the most I have done. Any help or suggestions would be greatly appreciated.
__________________


Nikko TRM-750 Integrated Amp
Kenwood KT-4007 Tuner
JVC TD-W805 Cassette Deck
Pro-Ject Debut III with platter upgrade
MB Quart QL-C200 loudspeakers (made in Germany
Reply With Quote
  #2  
Old 09-03-2007, 08:53 PM
jguzman21's Avatar
jguzman21 jguzman21 is offline
Large Member
 
Join Date: Dec 2002
Location: Georgia
Posts: 1,713
I believe AK'er brainsmasher has a pair of these. I also think he had one of the power supplies rebuilt. If they are the same model they are a fantastic sounding speaker.

-j
__________________
PSE Studio One preamp
OPPO DV-980H
Sony PS-X5
Magnavox Amp 175
Yamaha NS-1000M & Phase Research Model R
Reply With Quote
  #3  
Old 09-03-2007, 09:00 PM
Stereoholic Stereoholic is offline
AK Member
 
Join Date: Aug 2005
Location: Southern Wisconsin
Posts: 509
I have a pair, too, and would be interested to know how this turns out. I had one of mine open when I first got them (six years ago)- the power supply was fairly simple, if I remember right.
Reply With Quote
  #4  
Old 09-03-2007, 09:34 PM
clydeselsor's Avatar
clydeselsor clydeselsor is offline
AK Subscriber
 
Join Date: Jul 2007
Location: N.W. Indiana
Posts: 10,683
Quote:
Originally Posted by Stereoholic View Post
I have a pair, too, and would be interested to know how this turns out. I had one of mine open when I first got them (six years ago)- the power supply was fairly simple, if I remember right.
I haven't opened mine yet. I will work on these this week and let you know how it goes.
__________________


Nikko TRM-750 Integrated Amp
Kenwood KT-4007 Tuner
JVC TD-W805 Cassette Deck
Pro-Ject Debut III with platter upgrade
MB Quart QL-C200 loudspeakers (made in Germany
Reply With Quote
  #5  
Old 09-03-2007, 09:55 PM
wilke87's Avatar
wilke87 wilke87 is offline
AK Member
 
Join Date: Nov 2006
Posts: 187
You can go tho the website justrealmusic.com, He builds and sells rebuild kits for electrostats.
Reply With Quote
Audiokarma
  #6  
Old 09-05-2007, 03:55 PM
ztatic ztatic is offline
AK Member
 
Join Date: Oct 2006
Location: Columbus, Ohio
Posts: 34
Z-NNN problems

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.
Reply With Quote
  #7  
Old 09-05-2007, 10:45 PM
Brian's Avatar
Brian Brian is offline
An Old Geezer
 
Join Date: Jun 2002
Location: Toronto On Canada
Posts: 14,555
My experience with these early JansZen type I panel systems has been the power supply provided the panels have arced to the point where the membrane is toast. If only using them occasisionally probably the PS. My Z412HPs went after only 2 years in storage after Don Kweiler rebuilt the crossover. Don was the last remaining JansZen guru and had the parts. His specialty was crossovers and he designed the 1`s used in the Z412HP. SAdly, he finally passed on a few years ago.
Reply With Quote
  #8  
Old 09-08-2007, 10:19 AM
ztatic ztatic is offline
AK Member
 
Join Date: Oct 2006
Location: Columbus, Ohio
Posts: 34
Not quite the last

Quote:
Originally Posted by Brian View Post
My experience with these early JansZen type I panel systems has been the power supply provided the panels have arced to the point where the membrane is toast. If only using them occasisionally probably the PS. My Z412HPs went after only 2 years in storage after Don Kweiler rebuilt the crossover. Don was the last remaining JansZen guru and had the parts. His specialty was crossovers and he designed the 1`s used in the Z412HP. SAdly, he finally passed on a few years ago.
Just want to correct most of that.

Don Kliewer (please note spelling, pronounced "Klure") changed the design of the original JansZen tweeter in ways that I would call less than perfectly advisable, but appear to have been relatively harmless. He unfortunately indeed died, in 2002, I think, of a stroke, but was not the last JansZen "guru". There are others, such as at www.janszenloudspeaker.com and at www.soundlab-speakers.com.

The tweeter panels in speakers from Neshaminy (Z-600, etc.) and Electronics Industries (Z-412, etc.) could not arc unless the insulation shrank away from the ends of the wire electrodes on both stators at the same spot. Although this did sometimes happen, it was not the usual failure mechanism. This is because, with intact insulation on at least one side, when the voltage approached arcing potential, the air in the gap would ionize, and this would reduce the field strength below arcing potential. With extreme overload, the primary on audio step up transformer would burn out, or the secondary would arc over and short out.

When panels did fail, the usual problem was the connection at the membrane coating, which was for some reason not permanent. The problem was made worse when not enough series resistance was present in the bias leg, increasing loudness somewhat, but allowing current flow at the membrane connection that would eventually cause the coating there to evaporate. This was not the same coating as was used on membranes in panels made by A. A. Janszen at his original company, JansZen Laboratory, before selling brand rights to Neshaminy at the end of the 1950's. His coating would not experience such damage, but this would never be tested in situ because his bias supplies would never allow current flow. Constant Q was crucial to linear operation.

The crossovers in these systems were ordinary, and not a common problem. The usual suspects were components in the high voltage bias supply and the audio step up transformer, as described in my previous posting above.
Reply With Quote
  #9  
Old 09-08-2007, 03:16 PM
Brian's Avatar
Brian Brian is offline
An Old Geezer
 
Join Date: Jun 2002
Location: Toronto On Canada
Posts: 14,555
The problem with tracking Art's was the multiple licensing he did as well as development done by the companies licensing the technology. The Z-600 was produced by Neshaminy and utilized the type I panel developed by Art. This panel design also was the panel used in the KLH Nine licensed to KLH and Art's only full range design. Art did not sell the patent to Neshaminy, only the an exclusive license to use the technology and name. After Neshaminy discontinued the woofer which was their hallmark they surrendered the license and Art started Janszen Electrostatic that produced the Z-210Z, Z-410, Z412, Z412HP, Z-824HP and later series. This was the last company that produced JansZen speakers. These all used Art's 2nd design, the type II panel. Don was an employee of Janszen Electrostatic until it shut down and he went on to Winslow Industries. When Janszen shut down he secured many of the remaining parts and for those of us who either knew or became aware of him, he was the source for rebuilds, parts and remaining point of historical information. I am not sure what you mean by Don changed the design of the panel. Don's involvement at Janszen was in crossover design, something he confirmed when I interviewed him. Art was the developer of both the panels we associate with his name per Don; sadly I could not confirm this in deposition of Art as at theat time he had no memory and deposing him was useless. I still have someware in my closed files the information sent to me by Don related to the company.

I do think we are saying the same thing about the failure but you are more technical in your explanation than I as I am not an engineer. I became involved with JansZen during the days of Neshaminy and was a dealer for Janszen Electrostatic having the honor to have owned a set of the ultra-rare Z824HP and still have a set of Z412HPs sitting needing rework.

Add to the confusion is that Art either with his lack of guidance also issued licenses to others and the technology was used by others without permission or taking a sub-license from Neshaminy which was questionable. His design was the basis of almost all US produced electrostatics either through a legal license arrangement, a sublicense or without. During the years during Neshaminy's production Art only produced or controlled driver production at KLH for the Nines. He was not involved in development and production again until Janszen Electronics was created.

The current Janszen company owned by his son is in no way connected to the old company and the son never worked woth or for Art. I contacted it early when it came to be and they were not supplying parts or providing service on the old products but that seems to have changed as I understand they now provide repair for the Nines. Not sure if others.

Type I panels had the arcing problem but seldom failed. This was the weakness of the type I design and the source of the reputation of electrostatics arcing. There was nothing worse for owners than a high humidity day. The Type II reduced this greatly but the design has 2 weaknesses: 1) the hv wiring is at the high point of the panel and hence is prone to having the insolation compromised and 2) it is wrapped around the outside of the plastic frame and was to be held tight and in place by the wrapping and the separators molded in the frame. Sadly neither did their job well and the wiring tended to be too loose and wore on the separators as well as wearing off the insolation. The panel solved the arcing but was more prone to catastrophic failure than the type I panels. Art was working on a resolution to this problem but he saw it as a production problem and not a design flaw about the time I left the industry. I am not aware he ever solved it.

I never experienced a failure with either type and never had a unit in for repair at any of my stores so all in all the panels were really reliable. Sadly this was not the same with their offshoots from RTR, Koss and others.
Reply With Quote
  #10  
Old 09-08-2007, 11:46 PM
Cosmos's Avatar
Cosmos Cosmos is offline
Speakerholic
 
Join Date: Dec 2005
Location: Ohio
Posts: 2,313
Quote:
Originally Posted by Brian View Post
I never experienced a failure with either type and never had a unit in for repair at any of my stores so all in all the panels were really reliable. Sadly this was not the same with their offshoots from RTR, Koss and others.
Brian,

Perhaps, in their earlier years, the Janszen panels were very reliable. However, in the 60 or so panels I have acquired within the last few years, approximately 70% have failed exactly as described by ztatic above. They have lost conductance from the center (membrane) connection post to the membrane. On all of the failed units, with the exception of 1, I have been able to restore performance of a weak or dead panel by bypassing this post somehow.. (I have tried various methods) In fact, the tweeter panels in the KLH Nines you gave me suffered the same problem.

Having played with several generation II panels, I have yet to see one unit have a failure. Further, the type II panel is capable of higher output. However, when working correctly, I prefer the sound of the type I panel despite its lower output.

It should be noted that measuring the voltage of a electrostatic bias supply has it's own serious difficulties as it has to measure the voltage without creating any load on the supply.

One of these days, I intend to take a day to go visit David Janszen (Janszenloudspeakers.com), son of Art Janszen, who is now building speakers in Columbus Ohio. He has been very gracious in helping me diagnose some of the problems I have encountered with my KLH Nines. Further, I hope that David decides to participate at the next AKFest in Detroit next year. I would love to hear his speakers. If they sound half as good as their lineage might suggest, they will be the hit of the Fest and perhaps the industry.

Further yet, as Ztatic mentioned, Russ Knotts (of Justrealmusic.com or eslrepair.com) is a great repair facility for repairing any electrostatic speaker. On his website, you can even find a testimonial written by me regarding his work. I have no affiliation, other than that of a customer, with Russ and I have great respect for his knowledge.

Either of those two organizations should be able to help resolve the Janszen Z-600 problem.

Clydeselsor, if I can be of help to you, please PM me.
Reply With Quote
Audiokarma
  #11  
Old 09-09-2007, 10:59 AM
wilke87's Avatar
wilke87 wilke87 is offline
AK Member
 
Join Date: Nov 2006
Posts: 187
A few comments and questions.First let me say Don was my uncle ,and this seems to be the most history I have seen on this subject. It would great info if you could dig up that information on Don I would love to read it Brian.That being said I have recently recieved a pair of z-2cf Janszens and they work but have a few concerns and I also questions.There is a light buzz in the woofers when not in use,have read other post and they say to move the power supply ,It seams the at times have a annoying highs until they warm up awhile . Now should I just get new power supplys and recap or go to just real music or someone else a redo the whole crossover and power supply. I would like to try these repairs myself but would nees help identifing what to replace. Also what amplifiers are reccomend for these keeping cost in mind.And finnally I have the panels that are grey in color in the z-2cf and another set of non working add on tweeters z-132s that are black,is this how they are identified by first and second design.
Reply With Quote
  #12  
Old 09-10-2007, 05:47 AM
Brian's Avatar
Brian Brian is offline
An Old Geezer
 
Join Date: Jun 2002
Location: Toronto On Canada
Posts: 14,555
My information was received from Don as to much of the later history in discussions as to the U.K. lawsuit. The information as to Art was received from a law firm engaged to interview and do the deposition. I am aware of the ERC and Acoutech and he was a consultant and not the core designer though his involvement with designing the round ERC tweeter on the 139 involved him rolling up his sleeve. The last time I saw Art was during the design phase and testing of the 139.

My discussions back then were that the Type II was Art's design, per Art and it was to correct the Type I issues. Maybe Art was taking credit back and and years later Don gave him the same.

Art never mentioned his son was involved and in doing the research for the lawsuit his name was never brought up by anyone interviewed. And in each interview a same or similar question was asked as to if there was anyone else that would have direct knowledge of the issues asked and if so whom. As in any research things can be missed or forgotten but it seems unlikely that his son was forgotten by so many.

The licensing issues were not gone to in-depth as they were not in issue but there was testimony related to them. The only license/patent issue was related to the bi-wire crossover introduced in the Z412HP and Z824HP as this was the style of crossover related to the suite and it was determined early on it has not been patented or licensed to or from someone. Don's statement was that Art conceived the idea but he developed it but Art never considered it patentable. I am not sure how that would reconcile with your statement of his not being involved with the company.

My expereinces with the industry go back to the '50s and I left in 1980. The lawsuit was started in the very late '80s. In the years since I left, the street experience with product will be affected by time. If you look at my writings I generally have a time caveat such as when in production, both were new, etc. My experiece with the panels dates back to only a couple of years ago when I was still seeing JansZens around on the used market and others were buying and fixing. However, most of the knowledge of the defective units were from the the period they were in production and we were a dealer. How they have weathered since for others.

Last edited by Celt; 09-12-2007 at 08:20 AM.
Reply With Quote
  #13  
Old 09-10-2007, 11:11 AM
Brian's Avatar
Brian Brian is offline
An Old Geezer
 
Join Date: Jun 2002
Location: Toronto On Canada
Posts: 14,555
The lawsuit was by a Japanese company against several UK companies related to a patent rught they claimed. In the defense, it was determined that the bi-wire crossover of the HP series predated the Japanese patent. The interviews and information from Don and others related to the discovery during the suit. The suit was finally settled as we traced shipments of HP series speakers to Japan through an importer and a set was located. This offset the claim under Japanese law.

Last edited by Celt; 09-12-2007 at 08:27 AM.
Reply With Quote
  #14  
Old 09-10-2007, 02:34 PM
centaurus3200 centaurus3200 is offline
AK Member
 
Join Date: Aug 2004
Posts: 562
i had Z-600 and tried to rebuild everything in sight to get the one's speaker's panels working again. never worked, must have been the step-up tranny. swapped panels and they were fine.

now i have Z-200. pretty early rare system. each has the 4-panel 130-U array slid into he back of each dynamic woofer cabinet. worked until one started arcing. promptly shut them down.

replaced the crossovers and rectifiers. started working again, then one blew a fuse. put them in the garage for now.

when working though, they sound other-worldly! simply magnificent. but they are finicky to say the least.

one thing of note is that the power supply and transformers on the Z-600 are a joke compared to the 130U in my Z-200. and the Z-200 PS is sorta hokey too.

see ya,
Robby

Last edited by Celt; 09-12-2007 at 08:27 AM.
Reply With Quote
  #15  
Old 09-10-2007, 03:09 PM
wilke87's Avatar
wilke87 wilke87 is offline
AK Member
 
Join Date: Nov 2006
Posts: 187
Hey I was just looking for a little direction also for repairing my electrostats. I thought I have read on the new Janszen loudspeaker website in the history that electronic industries was the only electrostat panel that was somewhat endorsed to have been ok.Just a note to add that Don was more than a plastics guy he was responsible for many electronic inventions ,was a master at crossovers and had built many high quality speakers in his time.
Reply With Quote
Audiokarma
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 08:03 PM.



Friends of Audiokarma
We appreciate your help in keeping this site going.
Wargos Electronics
Amps and Sound
Sonneteer
Organ Donor Parts
Sound Stage Direct
Parts Connexion
AudioClassics
Atlantic Systems
AV Solutions
Take Five Audio
Tone Arm Audio
Audio Salon
Musical Paradise
Audience AV
Classic Sound Repair
Simply Speakers
McIntosh Cabinets
BD Enterprise
Cabledyne
Howard Products
BOI Audio Works
FM DX Antenna
Amplifiedparts
Siliconray
RSL Speakers
Vinyl Magic Record Cleaner
Urban Antigue Radio
Grant Fidelity
Many Moons Audio
Yesterday's Audio
The Tube Store
DeWick Repairs
Audio Doctor
Vintage Electronics Repair
MCM Electronics
Politicalchat.org
Herbies Audio Lab
Antique Radio Classifieds
 
Videokarma.org
   
Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
ęCopyright 2002-2014 AudioKarma.org, All rights reserved.