Selmer Treble 'N' Bass 50 MkII
Selmer's Treble N Bass 50 MkII arrived with some major changes to the MKI, the luxurious Truvoice croc-skin and gold disappearing to be replaced by a more austere plain black cabinet and a new grill cloth design. Major changes too in the position of the chassis – at the top and upside-down.
Part way through production, Selmer's lyre shaped logo appeared, looking slightly out of place and usually crooked, screwed to the front panel. It stayed there until the introduction of the MkIII.
A new and improved version of one of the most successful amps ever produced. 50 watts with such a wide tonal range that the amps is ideal for every use from bass to P.A. Twin channel, bass and normal, two inputs on each channel (high impedance) and separate Volume, Bass and Treble controls for each channel. Very smooth frequency response throughout the tonal range and superb performance without distortion at high volume levels. Separate mains and H.T. fuses. Cabinet finished in black with white trim.
No. 7041 .. .. .. 55 Gns.
SPECIFICATION
Valves: 2 x EL34, 1 x GZ34, 3 x ECC83
Length 21", Depth 91/4", Height 91/2"
Mains Input: 210 volts, 230 volts, 250 volts at 50 c.p.s. by external selector plug.
Power consumption 180 watts.
Output impedance 7.5 and 15 ohms.
Two output sockets fitted for use with locking type jack to prevent accidental disconnection of speaker leads.
Variations
Part way through its production life, the MkII was given a new mains transformer, with its built in voltage selector only accessible by removing the back of the cabinet. This version also saw the return of the metal screen between the valves and transformers.
The external voltage selector on the rear panel disappeared and the mains cable entry point moved up to take its place. Circuit operation remained the same apart from different mains voltage options (110, 120, 200, 220, 240 instead of 210, 230, 250).
Oddities
In amongst the usual two versions there seem to have been a few odd chassis with the old transformer, no rear panel selector and an internal tag board hard wired to the mains voltage options. The serial numbers are in the middle of a normal production run, so no idea how they came about.
IMPORTANT: These drawing and notes are provided for interest only and are not guaranteed to be accurate. Use at your own risk and discretion. The equipment shown contains lethal voltages and should only be worked on by people with suitable training and experience. Schematics and layouts are typical but will vary.
PRINTING
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Use the print menu to print to A4 plain paper.
Selmer Treble N Bass 50 MkII Schematic
(See printing instructions)
Selmer Treble N Bass 50 MkII Chassis Layout (external voltage selector)
(See printing instructions)
Please Note: Wire colours can vary.
Selmer Treble N Bass 50 MkII Chassis Layout (internal voltage selector)
(See printing instructions)
Please Note: Wire colours can vary.
