Problems with high voltage connectors to the ESL's

        The very first connectors I used (on the Wright St. George ESL's) were manufactured by Millen for use on ham radio transmitters. They, unfortunately, CSA (quite properly) would not let them be used on consumer goods.  When Ontario Place invited us to bid on the sorround-sound speaker systems, we had to design a connector that could be manufactured quickly. We produced an in-line design that was five inches wide. It allowed sufficient clearance between all the high-voltage electrode and bias connections as well as allowing us to add two pins that were located at the extreme ends of the connector. We used them for an safety interlock.

        As they were mounted on the upper rear side of what we termed, the bin, and the ESL's were tilted down (directing the sound towards the patrons, it seemed a reasonable and cost effective choice. It allowed us to employ male 'banana plugs' on the ESL's.

        When we had to switch to consumer goods, we could not afford a redesign of the connector. Therefor, we reinforced both the front and the rear with Delrin (tm) strips cemented to the vacuum-formed 'bin'. As soon as we were show a small recovery from the loss on the Ontario Place project, I designed a connector that would allow us to use commercially available mounting hardware (from AMP) by having our own connector block molded to fit the AMP shell. The pins were - Male 66242-2, Female ????. They were roll formed and were self aligning as both the pin and socket were sprung. We had to pre-seal both the pre-wired cable and ESL case wires so that the urethane-modified epoxy (which was 'water-thin') couldn't flow down into the rest of the connector. This allowed us to employ a 'pot' on the interior sides such that the stranded wires would also be sealed. As the pot was deep enough, when it was filled, it formed an insulating seal.

        The material employed in the 'block' molding was also critical. As I had some experience with SF6 underground insulated HV transmission cables, I knew that SF6 under extreme arcing, tends to decompose, forming trace amounts of fluorine. Therefore, the use of glass filled molding compounds is not wise. We used a a special non glass filler. Otherwise the pin will corrode and break off. As both the male and female parts of the connector are hollow, it is critical that there be no leaks whatsoever.

        We were able to have an initial connector-block  run of 250 comprising both the male and female pieces molded for us at Dayton Wright Associates Ltd., before the die set was fully hardened. Then it had to go for heat treating and relapping before we could use it in full production. When it was ready, we had another run of 100 sets made. There were some minor problems in the parts not ejecting properly, and it had to be sent back to the die maker for adjustment of the draft angles. It was then sent back for the first production run of 5,000 sets.  However the plastic molder we were using, had been sold and moved out of the Toronto area. Some of the customer-owned die sets were misplaced during the move. This was a minor disaster!

        We had to resort to casting connector blocks ourselves bu making silicone rubber molds. The resulting castings were somewhat brittle, as we were limited in the filler we could use. We finally recovered the dies and started to mold connector shells. But during the shipment of the dies, they had suffered damage causing one of the die inserts to crack. Again there was a minor delay.

        In the interim, one of the shareholders sold his shares to Klaus Behnke.  Production started again.

        In May 1976, Behnke attempted to sell the company to Leigh Industries. This is covered in the History & Background section. After Leigh moved the company to Waterloo, they found that they had, in their rush, lost the connector blocks. Leigh's Purchasing Dept., told them that it would take from three to five months to have a new set of connector blocks molded by a local firm. Before Leigh had moved us to Waterloo, I had obtained a quote from a Missasaugua company that was set-up for short (under 5,000 pieces) production runs.  What Leigh had been told was unacceptable. I telephoned a friend with the company that was producing the plastic I needed, then I checked-out the die-set myself, picked up two 45 Lb. bags of plastic, and took them to the molder.

        Three days later I took enough parts back to Leigh, that they could resume production when the were able. Within a week I returned the die-set and two cartons of connector blocks. I was read the riot act at Leigh even though I had taken the precaution of telling the Purchasing Dept. that they could take the credit. As I had asked the molding company a favor, I had to pay their bill.

        When I bought the company back in 1989-90, and had to move eight trailer loads of stock, I was amused to discover that the two cartons of connector blocks were still unopened. Before I tries to use them, I took the precaution of having the compound analyzed. It was a wise precaution as Leigh had the connectors molded from a silica-filled (glass) compound. We had to scrap them all. With reference to the larger pin size; we were faced with almost seventy IM-10's from Leigh (most completed and packed), as well as some twenty-eight  IM-10's that had been returned from the dealers with various defects. We began to convert them to use a leaf tweeter (rather than Leigh's single piezo unit - which could depolarize at high levels); with a much simpler circuit board using a pair of 15/25 watt L-Pads to set the leaf tweeter level. This tweeter was mounted in the top-center of the steel cabinet; mounted flush with the front diaphragm. Both the rear connections as well as the tweeter case were sealed against SF6 leakage.

        In the interests of computability, I decided to drill-out some of the non-glass-filled connector blocks with the intention of using them  until I could locate the die-set at which time I could deepen and enlarge the 'pots'. Alas, neither Leigh or we could ever find where they were. They were on the list of tooling we had purchased, but we could never find them even though I tried to call every injection molding shop in the area and even visited the most likely locations.

        We were forced to drill-out the rest of the connector blocks.

The use of SF6 and Cabinet Leaks

        The use of SF6 as an insulating gas was deliberate. SF6 behaves more like an 'ideal', isothermal gas than perfluropropane - and we were concerned that some ESL user might try to substitute propane rather than use the more expensive perfluropropane. My apprehensions were well founded. At least three audiophiles that bought second-hand ESL's tried to fill  or top them up them with propane. There was enough air left in some of the ESL's that the speakers caught on fire with the first arcing!

            A remark that was attributed to Gordon Gow of MacIntosh, was in error. The 0.65 gauge type HS Mylar diaphragm, is not permeable to SF6 and shows only a very slight permeability to water vapor. Several sets of Dayton Wright ESL's survived floods. When the cabinet trim was shipped to their owners and replaced, either by their dealer or by themselves, the ESL's were fine. The speakers didn't leak. We used gas leakage test equipment that was able to detect leaks as small as 0.001 mL a day. It would take over twenty years for the leakage to be even of minor concern.

        Most leaks are caused by cats. I know that this seems weird, but it is true. Many cat owners do not realize that cats instinctively try to get away from the ground (or off the floor). Their back claws extend when they leap-up to the top of a cabinet. We used to tell customers or dealers, to look for small holes (usually in the front Mylar diaphragm) about from 6 to 12 inches down from the top of the speaker cabinet. These holes are the result of cats. Still, some owners still protested that 'their cats' wouldn't even think of jumping up to the top of any piece of furniture in the house. We had to remind them that as cats are nocturnal creatures, they are used to roaming around the area at night.

        If they are there, two inch wide Mylar tape will seal them. Apply a thin coat of Plyobond (tm) to the edge of the tape to prevent the tape from peeling back at the edge.

        Leigh subcontracted-out speaker stands to allow the ESL's to be tilted back. They were a design disaster! The ESL cabinets had to be supported by a 1 inch wide wood strip at the sides and at the front of the speaker cabinet. If anyone accidentally bumped into the speaker, they would fall off the stand - usually producing a small tear in the grill cloth and, in some cases, tearing the Mylar diaphragm in the process!

        Leigh eventually tried to correct this by letting their distributor produce his own stand. They were on ball type castors. They were even worse as the castors reduced the front-to-back stability even more.

        We offered an optional castor's mounting for the ESL's. They made use of the 1/4" Allen screws on the bottom of the steel cabinet, replacing the existing screws with longer ones that went through the 1 3/4 inch (wide) x 3 inch (high) x 14 inch (long) oak pieces (two of which were needed for each speaker) - the pieces projected 3 inches to the front of the speakers (they were tapered down at the front) allowing a stable platform even on castors.

Power Supplies

This is well covered under the 'History & Background'.

"Crank Letters and Reviewers"

        Every manufacturer is faced with the (usually small) number of customers who have major problems with literally anything that they purchase whether it is audio, TV, cameras, tools etc. Often their frustration is legitimate. We have all heard about "lemons". Like automobile, high-end audio/stereo equipment can contain "bugs".

        We expect this and, as an ethical manufacturer, we tried to do our best to rectify our customer's problems. Our Limited Warranty reflected this policy. However, it is human nature when something does not function in the way, however strange, that the purchaser expected, to either return it, or call the manufacturer. We tried to screen our dealers to make sure, in advance, that the salespersons were competent, that the store had a service department staffed with competent technicians. We attempted to make sure that any dealer did not sell store demonstrators an new (unused) equipment. As there was a conflict between shipping companies (when a store signs the way bill and the truck drives away - the store is responsible for any damage) and customers who expect equipment they purchase to be in sealed cartons (which lets the shipping company off the hook) we tried to make it plain to the stores and their customers, that if the apparatus is in  SEALED carton and they accept it without any inspection by the dealer, they have made themselves responsible for any shipping damage. But, most stores and manufacturers are reasonable in this respect and will try their best to solve the customer's problem.

        Notwithstanding this, some (thank heavens it in in the minority) will come on so strong on the telephone, that it is almost impossible to diagnose the source of the problem. All too frequently the equipment is second hand and was traded in when the original purchaser realized that he (or she) had damaged it. This is most prevalent in cone speakers. In spite of the sales brochure and the manufacturer's warranty sheets, we have seen (as an example) some LCM-1's returned for repair were not only the voice coils on both the woofer and tweeter burned out, but both the woofer's surround and the crossover network's components fried. Both inductors were so hot (from excess current) that the embedment wax would have been completely melted - the resistors were fried and even, in some cases, the 100 volt rated capacitors would be fused. Obviously when the customer told us 'my speaker has never been played that loud, or 'I only use a 30 watt power amplifier' something smells!

        We tried to ascertain the truth, which, as can be understood, could be difficult at times. Often, we would find that the speakers were trade-ins or used (and not under warranty) or the owner's son was playing 'rock or heavy metal' when his parents were away. I took a great deal of tact. We always had a policy or repairing anything we manufactured, IF the parts were still available. In this respect the majority of Dayton Wright parts were still in stock sixteen years later. We tried to reach a equitable agreement on the repair costs, and in 95% of the cases, we were successful.

        When the Bank called our loan after Revenue Canada mis-assesed Dayton Wright Group Ltd., over $55,000 + penalties, we had to hire a new auditor to review our books. When he sent Revenue Canada his audit, Revenue Canada realized that they actually owed Dayton Wright Group Ltd., over $12,000. However it was too late as the bank had put the company into receivership. We had no access to any parts until I was able to buy some of the parts myself by paying the Provincial Sales Tax and GST (Government Sales Tax) as well as the Bank loan and costs.

        As small manufacturers don't have the "clout" of larger manufacturers, they are more prone to being ignored by parts suppliers/parts, manufacturers. Therefore, it is vitally important  to have an excellent Quality Assurance program in place to catch suppliers/parts, manufacturers defects before the product is shipped.

        Often, before a new product is released for production, the, manufacturer may ship some pre-production units to dealers with the caveat that they are NOT to be sold. The equipment manufacturer reserve the right to have these pre-production units shipped back to the factory at the manufacturers expense. These pre-production units are NEVER sold.

        But sometimes dealers cheat, and the equipment is sold! Unfortunately some equipment reviewers, anxious to get the jump, condole this practice. Some well known audio publications feast on controversy. They are usually marked by the 'miracle-system-of-the-month' syndrome and have a tendency to rush into print, reader's correspondence without extending the equipment manufacturer the opportunity to reply! The cost to the manufacturer can be immense. In this case they are no better than the tabloids! For this reason, some manufacturer's cater to them. Usually the magazine's "technical staff" are that only in name as usually really qualified people wont continue to write for them.

        The editors of some of these publications, frequently alter the technical articles without realizing that they are altered the context. Either in this respect they show their own lack of technical knowledge, but sometimes it is deliberate - trying to stir-up controversy!

        These have a tendency to publish first - often subjecting the subject of the letter to having to wait until the next issue to reply. I have written over one hundred articles and reviews myself, so I know of what  I speak. Often, it takes me three to four times the writing time just to verify the facts. If I am measuring something, I measure it a second time. If it does not agree with the published specifications, I try to discover the reason for the difference. Sometimes it is a simple as a ground-loop. Sometimes I an picking up RF or beats in the RF spectrum caused by capactive feedback or interference from a broadcast station or a taxi.

        Then I call the manufacturer or the supplier. Sometimes it is a bad electrolytic capacitor or a cracked ceramic capacitor or even a resistor, these things happen. If I still meet evasion, I send or fax a copy of what I have written for a comment from the manufacturer. I append these to the review. Any publisher who wants me to write for them, has to agree, in advance, to abide by these rules. It is known as ethics.

        I will not allow my name to be used as the contributor of a review unless there is this agreement. As I sometimes have to use a 'nom-de-plume' for obvious reasons, I follow the same rules.

        But 'crank' letters still get published. Some editors know that where the matter involves a legal matter, we in Canada follow English law, which prevents us from commenting on the matter. US editors are not -- by publishing 'a letter to the editor' they effectively transfer the responsibility, to the letter writer.

    In the forty years I have been involved in audio, I have found that 98% of the time that I or my staff have had to spend on complaints involve less than 2% of the customers. And about 60% of these cannot be be satisfied no matter what is done. It is sometimes linked to an ill-advised accommodation sale. But most of these people have had to lie to the dealer - for example - by representing themselves as audio engineers or recording engineers - rarely recording artists.

        One typical case, involved a 'contractor' for a recording company, (it later turned out that hr had designed a couple of record jackets for the art director of an agency) - we shipped him a set of XG-10's on an accommodation sale price (70% of our wholesale price) on the understanding that an qualified engineer from the recording company would set them up. He told us that the system was delayed for three weeks in the trucking company's warehouse  and blamed us for using a lousy trucking company. Then he said that were damaged upon arrival even  though they were shipped steel banded to a pallet.

        We checked with the trucking company - he had signed for them three weeks earlier and had set them up himself.

        It turned out that there was no engineer! We found out later, from a dealer in New York City, that he had returned every piece of equipment the dealer had sold. But this wasn't an isolated problem. Most of the dealers had him on their 'back list'. We were told by the same dealer, that he had painted his listing room black, he had a history  of getting drunk, dimming the lights, cranking up the volume  and too often he had had passed out from drinking wine. He was using a 1000 watt stereo power amplifier. However, we didn't find this for almost two years!

        In the meantime, we had replaced or rebuilt his XG-10's three times. Every time he blamed a trucking company. We told him that we had been more than reasonable considering what we had found out from the dealers in New York. He had an extra XIM-11 as well.

        We then told him that we would replace only the speakers one final time. However, this time he would have to come to the plant in a station wagon or a van, he had to listen to the speakers in our sound room, and stay as we packed his system. Our staff would load the stuff,  and that would be it - forever.  We were going to charge him $1,500 US which was the wholesale price but we wanted a certified check - he would have to take care of the duty. He agreed.

        Everything went as planned - until we found out he had rented a compact car at the airport - and he wasn't authorized to drive even that in the US. We made arrangements ourselves to rent him a van - until we found out that we were supposed to pay the rental and the insurance ourselves. No way.

        So we had to ship the speakers - but there was more. He had switched checks when I had left the room to arrange the rental and one of my staff had spotted this! But it was too late as he had left an uncertified check for $1,000 when he left the plant. We had the trucking company move the shipment to their warehouse. We reached him on Monday and told him what we  had arranged. He still owed us $500. The trucking company would be allowed to ship the speakers to the US when his checks had cleared the bank.

        More problems. He insisted that his XIM-11 was defective. So we shipped him another. Then we found that he had already sold his supposedly defective system for over $2,900 and his customer was happy. He agreed to return the extra XIM-11 to our New Jersey dealer.  We thought that the matter was finally put to bed. We had taken the precaution of sending him an invoice for the wholesale price of the XIM-11 providing it was returned undamaged within 90 days.

        He now threatened to lay a fraud charge against the company. An officer came by the plant and we showed him the whole file. He told us that were dealing with a 'nutter' and the Brooklyn police had a file on him, he would call them and say that we had been more than reasonable!  But the guy didn't return the XIM-11. Instead he launched a lawsuit. During all this time I was following the advice on  my lawyer. Our total costs to that date were over $65,000! While this was proceeding, he kept bombarding the stereo press with garbage as he had been making telephone calls threatening to force us into bankruptcy. It got so bad that even the phone company who had been monitoring  the calls (and couldn't act on a call from the US advised me change my home phone to an unlisted number.

        The the same sort of thing happened in Arizona. We had dropped off a SPA preamplifier at a CES  show. The customer had a lighting strike on his power line. He had no homeowner's insurance

Our warranty explicitly excludes lighting damage as even though  it might blow several capacitors or transistors, another component could fail as the strike over-stresses the other components as well!

        We explained this both to the dealer and his customer who launched into a tirade. Oh God - another nut-case! He immediately started calling the plant and the dealer. He bombarded every stereo magazine he could get his hands on, with hate-mail. I started to get calls from all over the US. His dealer had shipped the preamp back to the plant. We had explained to him as we would normally replace all the circuit boards and bill the boards at our cost - about $150. Neither the dealer or his customer would agree. I told the dealer maybe we might be able to do it as a time-filling-in basis when our staff had some free time. As the preamp might fail on noise testing during the two week burn-in, we could not do it on a rush basis. Every time a low-noise transistor failed - it would have to to be located and replaced and the burn-in started again. Finally it just passed specs and was shipped to the dealer by Emery Air Freight. US customs called the dealer several times. I called the dealer as well.

        We had already sent the dealer a copy of the warranty as well as including the warranty with the preamplifier. In both cases we had highlit the applicable warranty clauses as well as sent a letter to the dealer (the same letter was included with the preamplifier.

        The dealer called us again to get another copy of the warranty and we informed him that we had already sent him a copy seven weeks earlier, but the preamplifier also contained the same thing. If he could find the time to sign it through Emery Air Freight and Customs, everything was there!  Eventually it was shipped back collect. The front panel was badly bent as the dealer had left it there for four months.

        But the dealer became abusive and when he threatened me with what amounted to blackmail by sending letters to all the audio magazines in the US, I told him that we had already done far more than was reasonable and told him to 'Go to Hell!'

        We also reported the dealer to the OPP. They came to our plant and we gave then copies of the letters re the dealer and his customer. They were going to open a file and asked us that we should give them any letters that were printed. They would inform the proper persons in Arizona. The dealer had a letter published in at least three audio magazines.

        The dealer was sued and the case was dropped as the warranty was explicit.

        But a lot of audiophiles still remember. So do I.

       Over the years, many conscientious manufacturers have grown  tired of chasing dealers for payment on their invoices. Most of the people I have dealt with have their own horror stories about being squeezed between their banks and their dealers. Some have gone on to fields where they receive professional treatment by their customers. Where invoices are paid on time and the harassment by extremists is in the past!

        But others have succumbed to the stresses of the field and have heart heart attacks or died!


We have to apologize for the extremely long time that the .gif's and the .jpg's take to load.
When I have completed the scanning of the 35 years accumulation of drawings, schematics and other materials, I will start to replace the slow-loading files with much lower resolution interlaced gif's - linked on a graphic by graphic basis to the high resolution graphic that are now there.


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