DW AutoSound

Amplifier Top
50 watts per channel

        The power ratings were 50 watts RMS, 200 Watts RMS and 1,000 Watts RMS (Per Channel).

        We built several prototypes in tree different power amplifier capacities, 50 watts RMS, 200 Watts RMS and 1,000 Watts RMS (Per Channel); and made sure that the autosound group did not order more electronic parts than were needed for five prototypes. An exception was necessary for the aluminum extrusion. Here, as a special extrusion tool was needed, I had to design the extrusion cross section and have it approved by Renold's Tool makers before it could be made. Renolds Aluminum had to place an order for about $12,000 of the extrusion and most of it had to be paid in advance. The production run was a success, and some of the extrusion was cut into the lengths for the smallest of the three sizes. This was anodized in a satin black. A number of the extrusions were cut for the 200 Watts & 1,000 Watt power amplifiers. The silk screens were produced for all three of the units. A prototype run of the PC boards; limited to five, was made and silk screened for the resist and the parts locations. As I expected, some parts that were used for the testing of the physically oversize 50 watt running power amplifier were not available. as an example, Phlilips altered the design of the capacitors used in the power supply by reducing the size. This was OK as I had drawings of the revised design and the PC boards were made to the revised outline.

        I had incorporated a level control as well as three frequency settings for low, mid and high. The left and right channels were separated. I made these settings so that plastic pop-on fittings could be used to block access to these controls. However, we were going to offer control extensions for the installation people. The higher power units would offer a four position crossover switch with the option of operating these units only for subwoofers. In these cases, the 200 and 1,000 units could be set to cut off the higher frequencies so that an essentially class D operation would ensue. By eliminating the higher frequencies a significantly higher level of the sub-woofers could be maintained without overheating. This could allow a stereo pair of 1 kW power amplifiers to be used only for the sub-woofers and the lower power amplifiers to be allocated for surround and direct sound.

        I must admit that I had reservations about potential damage to the ears after I was exposed to several demonstrations.

        I designed the 1 Kw units to be 3/4 inch deeper than the 50 and 200 watt amplifiers. The reason was that the connectors for the DC supply were much larger. The same thing applied to the output connectors for the drivers. Elevating the bottom plate would allow me to include a forced air cooling fan that could draw in the air from underneath  the units as the bottom pan could be raised by 3/8 ths of an inch all the way around the power amplifier, We could offer a seperate pre-drilled (or pre punched) plate  that had a sixteenth of an inch of a ceramic heat barrier.

        Silver plated copper connections to the output bus' would present a design problem but the sectional drawings dispelled this. I had  to allow for the idiots that were sure to cram in way too much 'stuff' into too small a space. I knew from experience the stench of french-fried capacitors!

        However, the driver IC used the switching mode power supply was dropped from production and a new IC had to selected for the design. It's characteristics and even the 'pin-out' were different. The adaptation to the new IC took two and a half weeks; complicated by the lack of availability. Several large manufacturers had been working with the firm that designed the new IC, and, anticipating the savings, had altered their PC boards accordingly. These were receiving thousands of them.

        Unbeknownst to me, the firm that was going to produce the power amplifier, decided to order production quantities of the parts. The gold plaited  RCA type connectors did not meet specifications and were made of a cheap two piece cadmium plated connector that was only gold flashed. I had received this same type of cadmium plated connector and found that it was noisy, had severe RF interference because of the two-part construction, and when gold flashed, were even worse. I found they had ordered capacitors from a different manufactured and there was no way that these could fit under the extrusion.

        Then TONSIL altered their production schedule as AGDEVO's Roger Macpherson when he was in Poland, was two months late in signing the contract!

        It was worse than that,  AGDEVCO's Roger Macpherson had contacted Tandy Corp., Radio Shacks distributor in Barrie Ontario. When I went north  to call on Tandy's products manager (as Tandy - Radio Shack had expressed an interest in adding Stabilant to their product line), I saw that he had a sample of my the tweeter (from TONSIL) sitting on his desk. The DW part number was still visible as the black magic marker that had been used had not hidden our part number. When I returned to our Leslie Street office I took a chance and placed a call to George Bakers parts manager and asked him just how many of the TONSIL tweeters were in stock (I omitted the DW - the upper two characters - and used only our part number!) They had over 55 in stock.

        Understandably upset at this, I placed a call to ADVEVO's office in Saskatchewan and asked to speak to a company officer. I was connected about seven minutes later. I first told him who I was and explained that I signed, Canadian Government Approved Development Export License on my desk.  Did he have a copy available in his files?

        He did not, and explained that, no doubt that their Roger Macpherson had one. Then I stated that Roger Macpherson  had given a sample  to Tangy Corp., (Radio Shack), Barrie Head Office; suspicious, I had checked with Energy: George Baker's Company, and had called their parts manage in Markham. I was told that they had at least sixty tweeters in stock but he was expecting more within two weeks.

        I informed AGDEVCO,  that Roger Macpherson had  only 'faxed' me a copy of the document and said that he would mail me the signed document as soon as he returned to Canada.

        I told  AGED that my copy was signed in December of that year. By this time their were so many excuse for delays, that I stated  that I would have to check with Canadian Government Approved Development Export License office. I  said that I would call him back in the morning. When I was finally able to reach the proper office, I was told that they had sent a set of the blank documents to  Roger Macpherson, but they did not have any record of any such license being signed. They asked for the name of the person who had signed the document as it might still be on a desk of the official. The typed name was difficult to decipher from the fax and his signature was even worse. After a delay of several minutes (they had to look up their staff records), they first apologized for making me wait but stated that the didn't have anything in their files. To make it clear, I found out that there was no record of any such person.

        When I spoke to Davos office I told them that that Davos Roger Macpherson had given TONSIL all my proprietary drawings and design software without having a signed, Canadian Government Approved Development Export License. As I had made this a pre-condition for dealing with AGDEVO, I raised hell with them, as the value of all my proprietary drawings and design software, was based on six years of R&D work for Wright Electroacoustics.  This was worth an estimated $180,000.

        About a week later, I received an urgent call from AGDEVO. When the dust had settled I asked if they had ever run a due diligence check on Roger Macpherson before they hired him. No body seemed to know, but ADVECO assured me that it had been done. Then I informed them that I had placed several calls to used car dealerships and several seemed to know his name. I found that he was just a smooth talking salesman with absolutely no knowledge of import / export and the regulations involved.

    ADVECO seemed stunned; especially when I told them that not only had their incompetence cost me about $180,000 but it would cost other people in Ontario much more.

        As an example, I was told that Roger Macpherson had signed a deal with Russia to export tomato paste into Canada for (probably a Canadian manufacturer such as Libbey); however, as received, it did not pass inspection.

        I found out that I had to retain a lawyer licensed in Saskatchewan. When I retained him, in three weeks I found out that there were so many lawsuits already in file, I  might have to wait for several years; and, he gave his opion was a typical example of government lack of foresight rather than corruption.

        In 2001 I received a call from Saskatchewan. He said that it took him several weeks to locate me and another audiophile had told him about the Dayton Wright web site  So he was able to track me down. to inform me that a government warehouse had thousands of speakers on sale; these included woofers, midrange and tweeters. He had contacted me as my name was on the magnets of the woofers. I told him about the TONSIL problem and he conformed that, indeed, TONSIL was on some of several cartons.  He said that he would check to see if they were still available. Two days later, he said that the drivers had already been sold at an auction.


© 1989, 2003, 2006, Wright Electroacoustics

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