Magnatone Guitars!

New for Fall 2013, a complete guide to Magnatone guitars and the stories behind them!

1938-1960 Steel Guitars

1956-1963 Bigsby/Barth Era

1964-1966 Starstream Era


Magnatone Custom M8

Years 1963½-1964
Series Custom Series
Power 2x 7189A
Power Bias cathode biased
Preamp 7025, (1/2) 7025
Reverb (1/2) 12AU7, (1/2) 7025
Vibrato (1/2) 7025 (oscillator), 12AU7
Phase Inverter (1/2) 7025 for gain, (1/2) 12AU7 for paraphase.
Speaker 12" 8ohm Oxford 12K5R-7
Rectifier solid state
Output Trans8K:8ohm
Output 27 watts peak
Weight 37 lbs.
Height 23.25"
List Price $310

The M8 is a 2 channel 25watt amp with F.M.Vibrato and reverb driving a 12" speaker. The M8 is a M6 with reverb. See the M6 page for a description of the preamp, and vibrato.

While it resembles the bigger M10 in a few ways (12" speaker, vibrato, and reverb), the M8 uses a smaller, more economical 8K:1 transformer, a smaller weight speaker, and the two varistor version of the F.M. Vibrato. It is also a cathode biased circuit instead of the fixed biased circuits used on M10's.


The M8 reverb is different than the M10, M13, or M15 reverb. The schematics below show that one circuit drives the reverb tank with the cathode, the other with the plate.

early M8 Schematic
later M8 Schematic

The photo schematic was found at this cool amp site

M2 M4 M6 M7 M8 M9 M10 M12 M13 M14 M15 M10A M13A M15A M20




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