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 M10A

Years 1965-1967 (maybe as late at 1968)
Series Custom Series
Power 2x 7189A
Power Bias fixed bias
Preamp 2x 7025,
Reverb 12AU7, 12AX7
Vibrato 12AU7, 12DW7
Phase Inverter 12AU7
Speaker 12" 16ohm Oxford Alnico (spring-fall 1965)
Speaker 12" 16ohm Jensen ceramic C12PS (fall 1965 and later)
Rectifier solid state
Output Trans10K:16ohm
Output 38 watts
Price $380 (1965)
Price $395 (1966)
Weight 43 lbs.
Height 23.5"

In 1965, the M10A was introduced as a replacement of the 1963-1964 M10. With a speaker change and a preamp overhaul, the amp much more attractive to guitar players, and a much better competitor to the Ampeg Gemini I. While the M10 was one of the most popular Custom Series amplifiers, the M10A's demand made it an enduring favorite until some time in late 1967, or possibly early 1968.

Speaker Change

For the guitar player, the most significant change of the M10 to the M10A was the replacement of the Oxford 8" speaker and a 3" tweeter with a single 12" speaker. The first M10A's came with Oxford Alnico's. In the fall of 1965, Estey switched to 12" Jensen C12PS ceramic speakers.

Preamp Change

There is also a subtle but important difference in the preamp sections of the M10 it's successor, the M10A. Both have a three position "contour" switch, but while the M10 places this switch circuit directly after the first preamp stage, and the M10A places it after the second gain stage and uses a more complex set of RC circuits to affect tone. These added RC networks require a third stage 12AX7 to make up gain before heading to later parts of the circuit. So, while the M10 requires two 7025 tubes for its two preamps, the M10A requires three 7025 tubes for its two preamps.

I think this preamp circuit might have first been used on the 1959 190 "treble plus".


The Recovery transistor in the reverb circuit is replaced by a tube. This is similar to the reverb change made from the M15 to the M15A.

Color Change

Like all Custom Series amps left in the catalog for the 1965 re-vamp, the gold control panel and gold grill cloth is changed to a polished aluminum look with silver grill cloth.


This is a dealer brochure from sometime in 1966 showing what the dealer paid, and what was suggested for a retail price. The nickname, "The Wrecker" was light-hearted and aimed at a youth market.


Incredible product placement by Magnatone. Four happy nuns with Starstreams and an M10A





Except where otherwise noted, text/written content on this site is licensed under a Creative Commons Attribution 3.0 License.
Creative Commons License

web mechanics: text-to-html with Markdown, css handled with Blueprint, glued together with PHP