The McIntosh MC3500 Power Amplifier Mk II is a 350-watt vacuum-tube monoblock inspired by the original MC3500 while using current McIntosh protection and connection systems. Eight EL509S output tubes feed a Unity Coupled Circuit Output Transformer with dedicated 2-, 4-, and 8-ohm connections.
Three 12AX7A tubes serve differential-input, buffer/driver, and voltage-amplifier functions, with one 12AT7 assigned to an additional buffer/driver stage. Power Guard Screen Grid Sensor, Sentry Monitor, balanced and unbalanced inputs, and front-panel metering support operation in a matched monoblock system.
Three Important Features
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350-watt tube monoblock: Each chassis powers one loudspeaker channel.
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Unity Coupled output stage: Dedicated transformer connections support 2-, 4-, and 8-ohm loudspeakers.
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Current protection systems: Power Guard Screen Grid Sensor and Sentry Monitor supervise the tube amplifier.
Three Important Specifications
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Tube complement: Output: eight EL509S; small-signal: three 12AX7A and one 12AT7, with McIntosh-specified input, voltage-amplifier, and driver roles.
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Power output: 350 watts into 2, 4, or 8 ohms.
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Frequency response: +0/-0.5dB from 20Hz to 20kHz; +0/-3dB from 10Hz to 70kHz.
