Power amplifiers should be boring. They have a single, well-defined function: Make the input signal large enough to run a loudspeaker so that it makes sound at levels suitable for listening to music. Generally, controls and features are few or none. Peter Walker of Quad famously defined the ideal amplifier as a “straight wire with gain.” That’s just one feature: gain.
That ideal is not easy to achieve, for many reasons. Even a straight wire of any practical length and structure has properties (resistance, capacitance, inductance) that can affect how the signal is transferred to it on one end and how the signal is transferred from it on the other. These effects can be within the audible range depending on what device is at each end. Insert a complex device like a real-world amplifier (with different wires in and out) and Walker’s ideal starts to seem unrealistic, although it should be possible to get close.
Walker further stated that an “audio power amplifier is required to produce an output signal that differs from the input signal in magnitude only.”1 In attempting to realize that goal, he tried both tubed and transistor designs (although he averred that the latter were superior). Today, with the availability of tube amps and an expanding range of solid state designs, we have a broad range of options but no better standard than Walker’s.
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German kitchens, Japanese amps, and Afropop gems
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The Butthole Surfers wipe out
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Here's a hard truth: A written review of a full-sized speaker any speaker, really-is, at best, semi-useful. We all listen differently, we have different musical tastes, our system electronics are different, and our listening rooms vary a lot. You will gain a general picture of a speaker's capabilities and foibles from John Atkinson's measurements, and I can tell you how the speakers sound to me, in my room. But that's it. You need to hear them for yourself before making a buying decision. The best I can do is tell you how my music brain felt when the speakers were in my house and making music.
STEREOPHILE'S 33RD ANNUAL - PRODUCT OF THE YEAR AWARD 2024
When Stereophile's Product of the Year Awards were first published, in 1992, we decided that unlike some other publications and their awards schemes, we would keep the number of categories to a minimum. That way, we would avoid what the late Art Dudley once described as the \"every child in the class gets a prize\" syndrome.
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Mobile Fidelity, PrimaLuna, and First Watt redux
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