WOPL conversions on Dual 500?

NavLinear

NavLinear

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grapplesaw said:
That's right. But at two ohms it is at much lower power and there are 36 tranistors to share the load

Here is an other image of the transformer

http://sub.basspig.com/basspig/images/D500_interior1.jpg

There was one 2 ohm 700 series one built. It is story in it's self for an other day. Bob built it for my brothers company and drove it up to Vancouver but they did not want it. So my brothers friend bought it and Bob got enough money to get back to the USA. I believe it still lives on in Ottawa.
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That D500 is crammed packed - not anything like the 700 or 400 amps. Maybe one of the 500s will show up with a good price tag but most sellers seem to know that they are rare as hens teeth.
 
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laatsch55 said:
What was your brothers company?
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He worked for Dave Zephyr. They both started out at Kelly Deyong Sound on 4 th ave.
Dave bought all the pa from them and ran the business on his own. The 2 ohmer was in the early days of the Kelly period. It was a simple discussIon which ended up with Bob building something without an order. They had about 10 phase liners at the time. 1970 or 1971 I think.
 
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laatsch55

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Ed supplied me with some schematics of a Kelly Deyoung amp that was built to their specs , but it was a later date than that.
 
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Gotta hit the rack, up at 5 again....thansk Glen....we're going to have some interesting conversations I think....
 
NavLinear

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Glen is a cool dood - this is a Ben word. A bit more of the PL history has arrived at Phoenix.

Damn this cinnamon whiskey has kicked my ass.
 
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NavLinear said:
Glen is a cool dood - this is a Ben word. A bit more of the PL history has arrived at Phoenix.

Damn this cinnamon whiskey has kicked my ass.
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You're getting closer to chick drinks every day.....so you can quit making fun of my "Fuzzy Baileys"...
 
grapplesaw

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laatsch55 said:
No Glen I do not have one. I was talking to Ed on the phone one day and the subject came up. Ed says a 700 transformer will fit in a 500, I'm assuming the reverse would be true...
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I was thinking today about this swap. The 700 Transformer may fit in a d500 physically but it doesn't put out the 120 volt rail voltage nor can it supply the additional 85 low rail voltage. It would be a detuned 100 volt rail at best.

Lee do you know what the unused wire on the 700 transformer is able to put out? It is not connected to anything. Just there minding it's own business and bothering no one.

I though of some internal fans may be a good idea.
 
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laatsch55

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Which wire Glen? And I was thinking about going with the 120 rail voltage 500 in the 700. With the MJ21196's , they might hold up....I've thought about it too. That's what led to the monster mono idea. The idea behind the monster monos was to drive a low ohm load all day long at hi power levels. The power supplies on the monsters are going to be built so I can add 2 more toroids per channel if need be...

If you put a 700 tranny in a 500 you would at least be able to spread a low ohm load over more outputs..
 
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laatsch55 said:
Which wire Glen? And I was thinking about going with the 120 rail voltage 500 in the 700. With the MJ21196's , they might hold up....I've thought about it too. That's what led to the monster mono idea. The idea behind the monster monos was to drive a low ohm load all day long at hi power levels. The power supplies on the monsters are going to be built so I can add 2 more toroids per channel if need be...

If you put a 700 tranny in a 500 you would at least be able to spread a low ohm load over more outputs..
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I agree with you on that. I have a repair manual for it. Do you have a vault for that here?

If I read the following right 120 volts is well within the mj21195 limits
http://www.onsemi.com/pub/Collateral/MJ21195-D.PDF

The 2 ohm unit I talked about put out 700 watts at 2 ohms. I do not know how this was done.
 
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It could probably be done by altering the parameters at which the protection circuit shut down the base drive voltage. Joe has done that to some extent with the ew boards but was reluctant to take it to the edge of the 21196's SOA as his board was a universal replacement and some would still run the XPL-909's , causing Joe to leave the protection circuit pretty close to what it was. But that can be messed with and altered , I'm thinin that may have happened to the Series one 700 you refer to. Nothing else culd really do that leaving the basic design intact. With adequate cooling it could be done...
 
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700 watts at 2 ohms is not that difficult to do. the 700's I've tested into 4 ohms at 775 watts per channel. 700 into 2 ohms PER CHANNEL is doable.....
 
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grapplesaw said:
I agree with you on that. I have a repair manual for it. Do you have a vault for that here?

If I read the following right 120 volts is well within the mj21195 limits
http://www.onsemi.com/pub/Collateral/MJ21195-D.PDF

The 2 ohm unit I talked about put out 700 watts at 2 ohms. I do not know how this was done.
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It is not 120V it is 2X 120 volts (240V) that you should be concerned about. At 240V Vce, the MJ21196 will tolerate 600mA per device for 1 second at a Tj of 200C peak.

The original PL909 would have been toast long before that.
 
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