Selmer Treble 'N' Bass 50 MkIII
The MKIII Treble 'N' Bass 50s came with solid state rectifiers (instead of the GZ34 in the old MkIIs), a new Echo In/Out feature, an internal mains voltage selector, two cabinet designs and at least four different wire colour schemes. (That's why colours aren't shown in the layout drawings).
Rectifier types varied and the filter capacitors changed from 16uF to 32uf at some point. One notable change was in the layout around the Echo In/Out circuit. Early examples may have C11 mounted on the board through an extra eyelet, while on later versions it sits between the board and the Echo In socket. Makes no difference. The circuit is the same.
After sixty years, like most things, a lot of them will have been dropped, repaired, modified or hacked about. Watch out for dubious mains cable connections. Very nice amps and well worth bringing back to life.
Corrections / comments welcomed.
PRINTING
Wix only provides .webp images at the moment. To make a hard copy of a drawing :
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Left click when the magnifying glass icon appears and wait for the picture to clear.
(On a touch screen, tap on the image) -
Right click and 'save image as' to somewhere as a webp file.
(On a touch screen, touch and hold down to view the menu) -
Open the saved file with 'Photos' (Windows 10) or whatever app works for you.
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Use the print menu to print to A4 plain paper.
Selmer Treble 'N' Bass 50 MkIII Schematic
Component ID numbers are for convenience only. No factory numbers available at the time.
Selmer Treble 'N' Bass 50 MkIII Under-Chassis Layout (Early)
Selmer Treble 'N' Bass 50 MkIII Under-Chassis Layout (Late)
Selmer Treble 'N' Bass 50 MkIII Above-Chassis Layout
