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Seven-valve amplifier

This is from the same spot (Makezine) that hosted Mr Still’s unicycle snow-chains article; it’s a seven-valve (counting the dual-half-wave rectifier valve as one valve, and counting a dual valve as one valve) monauraul audio amplifier built for Albert Einstein’s 70th birthday.

It’s a very simple, clean design (uses many dual valves, appears to have ClassB power output) but I shudder to think about items like intermodulation distortion, not to mention basics like hum, total harmonic distortion and pure efficiency.

It’s here because it makes an interesting contrast with (say) a fingernail-sized Flash media player or a tiny sound-card which not only does the same thing — in stereo or quad, at least — but almost certainly at a much higher quality.

(Possibly except for the actual music itself) it’s a reminder that the good ol’ days are good primarily because they’re old, so we don’t have to put up with them any more. Imagine how large your Athlon-powered... um, laptop would be with this techology in it!

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