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Heathkit AA-121

Stereo Power Amplifier

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Heathkit AA-121


The Heathkit AA-121 high fidelity stereo amplifier incorporates two complete amplifier channels and a common power supply which provides B+ voltage, negative bias voltage and filament voltage to both channels.

Each channel has separate input level and bias adjustment controls.

The function selector switch facilitates the selection of either stereo or monophonic operation.


Power output: 40 watts per channel into 8Ω (stereo), 80W into 8Ω (mono)

Frequency response: 20Hz to 20kHz

Total harmonic distortion: 1.5%

Damping factor: 16

Input sensitivity: 0.95V

Signal to noise ratio: 85dB

Speaker load impedance: 4Ω to 32Ω

Semiconductors: 4 x silicon diodes, 1 x selenium diode rectifier

Valve complement: 2 x 6AN8, 4 x EL34

Weight: 35.75lbs

Year: 1962


assembly and operation   English -

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