Neat 4-channel balance control: Hitachi

[winopener]

We all know the joystick-like balance control from several manufacturers... well, that's a different approach: rotatory l/r and slider f/b (images from a fleabay auction).
Don't remember to have seem anything like that before.

 

[Soundfield]

Amazing the lengths some manufactures went to in order to 'solve' that particular control issue. According to the service manual that arrangement required a combination of linear and rotary pots linked by a pivoting bracket:

I would imagine the mechanical play in that thing meant it was at best a rather sloppy control.

 

[winopener]

The big mess was just to move the light...

 

[Soundfield]

The big mess was just to move the light...

Yup, waggling a filament lamp around with that pivoting bracket and calling it a "Quadraphonic Balance Display" was marketing, if not engineering, creativity at its finest.