a question about amp conections
- Thread starter K-5BLAZER
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- Joined
- Jan 14, 2011
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- 74,877
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- Gillette, Wyo.
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- Halfbiass...Electron Herder and Backass Woof
WOPL Sniffer is thrifty with his words.
When you obtain (or drag it out of storage) a big Phase Linear amplifier, it is forty to fifty years old, having been originally released in 1972. We limit ourselves to the Phase Linear 400 and the Phase Linear 700 amplifiers in original and Series II flavors because these were the ultimate Bob Carver designs for loud, clear 'sound reinforcement' (we avoid the Phase Linear 200 and the later DRS Phase Linear amps released when Pioneer bought Phase Linear in 1979). In fact, many rock bands (Pink Floyd, Aerosmith, etc.) in the 1970's and 80's used the venerable PL700B in their stage sound setup. Unfortunately, these amplifiers had a tendency to 'latch up' in the front end, meaning the small signal transistors would turn on fully and allow the power supply voltage (75 or 100 Volts) to go directly to the speaker outputs, due to a tiny flaw in the Bob Carver design, and no one really understood why. This is the reason so many of these amplifiers were abandoned, speakers became more expensive and no one wanted to fry their new pair of AR, Polk, Advent, Infinity, Klipsch... well, you get the idea.
In the early 2000's, Joe, who owns and runs White Oak Audio, decided he could improve on the original Phase Linear design using modern components and computer-aided circuit design, neither of which were available to Bob Carver at the time. Joe offered these new amplifier Control Boards as an upgrade or to 'fix' a blown "Flame Linear" or "Blaze Linear" amplifier. We now have Revision G1 of Joe's original upgrade.
Due to Joe's excellence in audio and electronic engineering, the 'latch up' problem was solved and we often wonder if Bob Carver would have been the Bill Gates of stereo, if he had been able to correct this flaw in his design. He left Phase Linear in 1977 to form Carver in 1979 and then Sunfire corporation in 1994 and still designs amplifiers today. The last Phase Linear amp built was in 1983.
So, any Phase Linear 400 or Phase Linear 700 amplifier with a White Oak Audio Control Board is designated a WOPL, to give credit to Joe for improving the circuitry, and to Phase Linear for manufacturing the original product. Joe added bulk capacitors, new light bar designs, more rugged output transistors, backplane wire boards, faceplates, and even a new PL700 chassis to his list of products offered here:
http://www.whiteoakaudio.com/estore.aspx
When you obtain (or drag it out of storage) a big Phase Linear amplifier, it is forty to fifty years old, having been originally released in 1972. We limit ourselves to the Phase Linear 400 and the Phase Linear 700 amplifiers in original and Series II flavors because these were the ultimate Bob Carver designs for loud, clear 'sound reinforcement' (we avoid the Phase Linear 200 and the later DRS Phase Linear amps released when Pioneer bought Phase Linear in 1979). In fact, many rock bands (Pink Floyd, Aerosmith, etc.) in the 1970's and 80's used the venerable PL700B in their stage sound setup. Unfortunately, these amplifiers had a tendency to 'latch up' in the front end, meaning the small signal transistors would turn on fully and allow the power supply voltage (75 or 100 Volts) to go directly to the speaker outputs, due to a tiny flaw in the Bob Carver design, and no one really understood why. This is the reason so many of these amplifiers were abandoned, speakers became more expensive and no one wanted to fry their new pair of AR, Polk, Advent, Infinity, Klipsch... well, you get the idea.
In the early 2000's, Joe, who owns and runs White Oak Audio, decided he could improve on the original Phase Linear design using modern components and computer-aided circuit design, neither of which were available to Bob Carver at the time. Joe offered these new amplifier Control Boards as an upgrade or to 'fix' a blown "Flame Linear" or "Blaze Linear" amplifier. We now have Revision G1 of Joe's original upgrade.
Due to Joe's excellence in audio and electronic engineering, the 'latch up' problem was solved and we often wonder if Bob Carver would have been the Bill Gates of stereo, if he had been able to correct this flaw in his design. He left Phase Linear in 1977 to form Carver in 1979 and then Sunfire corporation in 1994 and still designs amplifiers today. The last Phase Linear amp built was in 1983.
So, any Phase Linear 400 or Phase Linear 700 amplifier with a White Oak Audio Control Board is designated a WOPL, to give credit to Joe for improving the circuitry, and to Phase Linear for manufacturing the original product. Joe added bulk capacitors, new light bar designs, more rugged output transistors, backplane wire boards, faceplates, and even a new PL700 chassis to his list of products offered here:
http://www.whiteoakaudio.com/estore.aspx
- Joined
- Jan 14, 2011
- Messages
- 74,877
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
Some may consider a 700B or Series II (and 400's) a WOPL if it has a White Oak Control Board, but myself, I don't consider it a WOPL until it's been rebuild with ALL White Oak Upgrades. i.e. White Oak Back Planes, AND a white Oak Control Board and wired according to the White Oak Wiring/Grounding scheme. Although, the White Oak control board gives you many benefits, you don't get the full "E" ticket ride until they are ALL implemented together. Throw in a WattsAbundant DC Protection board, a WO Light Board/Meter Boards and all the little bits of hardware and you now have yourself a contender (actually, it murders any other contender). Until you get rid of any vestiges of the original amp, you are waiting for a catastrophic failure which can cause damage to your speakers/amp/home................ A half upgraded amplifier, IMHO is NOT a true WOPL.................... But.... Then again, what do I know??? I have only built about 100 of them. 
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