700 Series II Build

Hexis22

Chief Journeyman
Joined
Dec 28, 2022
Messages
857
Location
Wisconsin
Started a 700 Series II build for new member @AKdeVo.

This build will include full White Oak offerings and all recommended updates:
- Full WOPL (Control board, Backplanes, New output drivers, Power supply caps, Rectifier)
- WO Cylon LED meters
- New Chassis and Black Faceplate
- Stainless electrically isolated transformer mounting bolts
- Billet knobs
- Speaker output DC Protection
- New RCA inputs
- Triac power switch

The donor amp was in excellent condition and a great overall starting point.

One of the cleanest all original 700 Series II's I've had on my bench.

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For those of you on the fence about upgrading these 40 year old amps, I present several examples of typical issues found in this design that I would NOT trust with my speakers or home for that mater:

Resistor and Zener voltage regulator on control board exhibiting thermal issues.

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Unsoldered lower AC mains fuse holder.

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Output driver mounting screws driven into interior components.

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Stranded wire potential shorts.

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WOW! Your bingo card is completely filled out!
My 700 had an unsoldered wire at the speaker output binding post- no other boo-boos.
 
Remnants after scavenging required components for new build. Everything pictured will be replaced with new components.

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Parts carried over
- Transformer
- Cap cradle
- Cap clamp
- Coupling switch
- RCA copper ground plate
- Bias transistor P-Clamps
- Transformer wire terminal strip
- Switch bracket
- Switch caps
- Cylon meter mid plate
- Heatsink fins (not pictured)

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