700 Series II Build

[Hexis22]

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.

 

[Hexis22]

A look under the hood showed the interior was just a clean as the exterior. This amp did not see much use!

 

[Hexis22]

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.

Unsoldered lower AC mains fuse holder.

Output driver mounting screws driven into interior components.

Stranded wire potential shorts.

 

[J!m]

Those aren’t flaws; they’re features!

 

[Hexis22]

Features at no additional cost with every amp.

One way audio service centers stayed in business back in the day.

 

[AKdeVo]

Can't wait to see you work your magic on this!

 

[MarkWComer]

WOW! Your bingo card is completely filled out!
My 700 had an unsoldered wire at the speaker output binding post- no other boo-boos.

 

[Hexis22]

Remnants after scavenging required components for new build. Everything pictured will be replaced with new components.

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)

 

[Hexis22]

Control and backplane boards assembled, cleaned, and inspected under magnification.

 

[AKdeVo]

Looking good!

 

[laatsch55]

Fuckin solder artist!!

 

[74sdta]

NICE work! Scary beginning but AKdeVo will have a masterpiece when done.

 

[Gibsonian]

Fuckin solder artist!!

A hot iron Picasso

 

[laatsch55]

Amen Scott!!!!

 

[Hexis22]

Clean robust solder joints and thoughtful wire placement are foundations for every good build.

 

[Hexis22]

New heavy duty switches mounted to bracket after marking and drilling holes.

 

[Hexis22]

Cap cradle updated with new rubber grommets, J-B Weld reinforcement and drilled out holes to accept bolt isolation bushings, and tapped for 10-32 rectifier mounting screw.

 

[Hexis22]

Housing assembly started with backplanes boards and heat sink fins installed.