M60

About the M60

The Sound Valves M-60 is a mono vacuum tube amplifier originally released in 1994, designed as a successor to the Dynaco MKIII. It delivers 60 watts per channel into 8 ohms and features a four-stage, single-channel power amplifier topology with an all-triode front end and Class A gain stage. The amplifier supports triode or ultralinear operation selectable by a switch, with pure Class A operation at lower power levels and Class AB1 at maximum output. It uses high-quality USA tubes (2 x 6550A/KT88, 1 x 12AT7/6201, 1 x 12AU7/5963) and custom-wound power and output transformers designed by Harry Klaus. The M-60 supports 2, 4, or 8 ohm speaker loads and includes visual bias adjustment for each output tube, soft startup for extended tube life, and a regulated power supply for front-end tubes. The chassis is a classic chrome-plated steel with a perforated "Ultra-Vent" cover cage. It is hand-wired point-to-point with precision components and military-spec parts for reliability and low noise. Dimensions are approximately 9.5" W x 7.5" H x 11" D, weighing 32 lbs. The amplifier is praised for its clarity, tonal accuracy, and dynamic headroom, with a signal-to-noise ratio better than 95 dB and total harmonic distortion around 0.5%.