WANTED: PL 700 II faceplate and knobs!

MarkWComer

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#5
Look in the parts archive, post #8, for some knobs. There may be posts for other knobs, too.
 

Schmurpy

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#6
Original Phase Linear knobs are hard to find. Are your controls solid shaft or flattened "D" shape?
I didn't know there was 2 versions.

I'm looking at a PL 700 II PRO model, which has the industrial looking black face, and smaller black knobs. If the sale works out, I want to convert it to silver face, and the corresponding knobs.
 

mlucitt

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#7
I didn't know there was 2 versions.
The earlier knobs, found on PL700, some PL700B, and some PL4000 were solid aluminum with set screws that would work on round shaft or flattened "D" shafts. The later, and far more common, knobs are thin aluminum that dents easily with a plastic insert that fits only the flattened "D" shaft.

Your PRO model had the least expensive Radio Shack black plastic knobs.
 

WOPL Sniffer

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#8
I didn't know there was 2 versions.

I'm looking at a PL 700 II PRO model, which has the industrial looking black face, and smaller black knobs. If the sale works out, I want to convert it to silver face, and the corresponding knobs.

Don't convert a Pro 700.... I'll buy it from you and build you a WOPL. I even have NOS 700 II faceplates
 

Schmurpy

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#10
Or, I have a 700B WOPL if you are undecided
I just bought 2x 700 II units, 1x 400 II unit, and 1x Carver PM 1.5.

Another member on here got to the 700 pro at the last second, which is fine; apparently they had their eye on it long before I knew about it.
 

George S.

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#13
Other than the black faceplate, and small plastic knobs, was there really a difference?
No, not really. No normal/direct switch on the back. Has a rack mountable chassis, and 1/4" input jacks instead of RCAs. Different attenuators.
But! For those people really into PL, it would be bad karma to put a regular face plate on a pro. Like Mark said, they're too rare. I feel somewhat conflicted as I'm planning to WOPL this one this coming winter. But after much thought it's the right thing to do as I want to use it.
 

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FredR

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WTF?
#14
The earlier knobs, found on PL700, some PL700B, and some PL4000 were solid aluminum with set screws that would work on round shaft or flattened "D" shafts. The later, and far more common, knobs are thin aluminum that dents easily with a plastic insert that fits only the flattened "D" shaft.

Your PRO model had the least expensive Radio Shack black plastic knobs.
Now that you are on this site your options just greatly expanded. Time for research.
 

mlucitt

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#15
Other than the black faceplate, and small plastic knobs, was there really a difference?
The PRO 700 was similar to the Clair Bros. Audio "Professional Sound Reinforcement" amplifier for commercial use.
The chassis is steel, which holds up better for rack mounting. It also acts like a magnetic echo chamber, but the effect is minimal. There are holes in the heat sinks to mount fan cooling.
The Zobel Network leading to the speaker binding posts is substantially enlarged to support full volume for long periods.
The outputs are 1/4" phono jacks for stage sound wiring.
The biggest difference is the amp is full-complementary, with both NPN and PNP output transistors.

I would install a WOA Rev G1 "Dual Mono" Control Board and a Watts Abundant DC Protect delay/relay board. Then I would change the input jacks to Manley Labs gold RCA jacks. I would test the output transistors but probably leave them if they were all good. If any tested bad, I would replace them all. This keeps the original 'look' of the amp while updating it and making it reliable.
My 0.02...
 
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