Selmer Treble 'N' Bass 50 R.S.V.
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Selmer Treble 'N' Bass 50 S.V.
Two channels (bass channel, normal channel). Two inputs per channel (high impedance). Volume, treble and bass controls on each channel. Two sockets at rear for connection of echo unit between pre-amplifiers and power amplifier. Also available with reverb.
Power output: 50 watts r.m.s.
Output impedance: 7.5 ohms and 15 ohms.
One carrying handle.
Cabinet finish: black, silver panel with black lettering, black and satin chrome trim.
TREBLE 'N' BASS 50
No. 7402 .. .. .. £74. 0. 0.
TREBLE 'N' BASS 50 with REVERB
No. 7403 .. .. .. £88. 0. 0.
1. Treble 'n' Bass 50 RSV
Although cosmetically one of the less desirable Selmer designs, this series are actually very nice, affordable amps. This particular R.S.V has been in the wars a bit and seems to have been fairly close to a fire judging by the melted control knobs and lack of covering material. It ended up living under some old engine parts after that.
This was just a 'get it going and make it safe' project, so no attempt to polish anything up.
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
Wix (bless 'em 😖) have changed their image format - again - to avif just to make them awkward to print. Unless you want to buy a converter, the easiest way to make a hard copy is:
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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). This will display a higher res file. -
Right click and 'save image as' to somewhere as an avif file.
(On a touch screen, touch and hold down to view the menu) -
Upload the saved file to your Google Drive.
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Open the file and use the print menu to make a hard copy or save as a pdf.
2. Selmer Treble 'n' Bass 50 RSV Schematic
3. Selmer Treble 'n' Bass 50 RSV Layout Below Chassis
4. Selmer Treble 'n' Bass 50 RSV Layout Above Chassis
5. A few 'after' pics (yes, I know the carpet needs hoovering)
Bearing in mind that this was just a 'get it going' project, it's had a very quick once over to the metalwork.
The Mains and Standby rocker switches had disintegrated and are modern replacements. Ideally they would be changed for NOS metal surround versions.
The pots feel rough, but they probably always did and they still work. Knobs are whatever came to hand at the time and, again, could be exchanged for something nearer the originals.
Despite what folks will say (including me sometimes), if the amp sounds fine and looks OK, it really isn't necessary to replace every capacitor in sight. It will be fairly obvious if they're past their sell-by date. This unit made power and just needed one new valve and attention to the wiring.
The power cable had a properly fitted 13Amp plug but was only a foot long (it may have been chopped off in the past if the amp was sold as 'parts only').
All of the mains wiring has now been stripped out and replaced along with the heat damaged cable to the Standby switch.
Through a decent cabinet it sounds the business and hopefully it'll be back out on stage for a long time to come.
6, Selmer Treble 'n' Bass 50 SV
Similar idea to the RSV with similar problems. This one had one completely dried out reservoir cap.
7. Selmer Treble 'n' Bass 50 SV Schematic
(See printing instructions above)
8. Selmer Treble 'n' Bass 50 S.V. Below Chassis Layout
9. Selmer Treble 'n' Bass 50 S.V. Above Chassis Layout
