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W3-AM Dual-Chassis 20-Watt Amplifier

W3-AM Dual-Chassis 20-Watt Amplifier


  • Power supply and main amplifier on separate chassis for installation flexibility
  • Uses acrosound "ultra-linear" output transformer
  • Williamson-type high-fidelity circuit
  • Matches speaker of your choice; 4, 8 or 16 ohms

The model W3-AM amplifier offers complete flexibility in custom installations. The power supply and amplifier stages are on separate chassis interconnected with a cable. These two units can be mounted side-by-side or one above the other as desired.

Employing the Williamson-type high fidelity circuit the W3-AM features the famous acrosound TO-300 "ultra-linear" output transformer and 5881 tubes for broad frequency response, low distortion, and low hum level. The result is exceptionally fine overall tone quality. Frequency response is ± 1.5 db from 20 cycles to 80 kc. at 1 watt output, with controlled rolloff about 80 kc to insure complete stability at high frequencies. Harmonic distortion is less than 1% and IM distortion is less than 1.2% at 20 watts. Hum and noise are 85 db below 20 watts. The output transformer has taps at 4, 8, or 16 ohms to match the speaker system of your choice.

Top quality parts are used throughout. No technical training or electronic background is required to build one of these high fidelity units. You can experience the emotional impact of true timber response, and you have the additional satisfaction of having "built it yourself". Assemble your own Williamson-type amplifier now for real listening enjoyment.

Specifications—Power Output: 20 watts. Frequency Response: ± 1.5 db from 20 to 80,000 cps at 1 watt. Harmonic Distortion: 1% at 20 watts. Intermodulation Distortion: 1.2% at 20 watts (60 and 6,000 cps, 4:1). Hum: 85 db below 20 watts. Damping Factor: 14:1. Input voltage for 20 watts output: .85 volts. Tube complement: 2-6SN7GT, 2-5881, 1-5V4G. Output Transformer: Acrosound type TO-300. Power requirements: 105-125 volts, 50/60 cycles, 120 watts. Overall Dimensions: 7" high by 5½" wide by 11" long. Shipping Weight: 29 lbs.

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