Apt Corporation Holman
Beschrijving / Description
The Apt Corporation's Holman Preamplifier is the most well thought-out stereo preamplifier ever designed.
It was designed at the very height of recorded music's reign as the dominant form of home entertainment (home video was still years away), and was designed by none other than the brilliant Tom Holman, the inventor of 5.1 audio and the inventor of THX motion picture sound.
More important than its stellar laboratory performance is the fact that this preamplifier is designed to do exactly what's needed to make music, and a music reproduction system, sound great. This preamplifier even has a patented variable stereo expansion circuit, a foreshadowing of Tom Holman's later exploits into multichannel sound.
It uses many ingenious and patented circuits. For instance, in addition to the stereo control, a brilliant volume control system actually varies the amplifier's gain for the best noise and distortion performance, instead of merely attenuating a larger gain as do other amplifiers. It allows us to control the level over a huge range with ease, and always keeps the channels perfectly balanced.
The unique tone controls adjust more precisely than ordinary controls. They are individually calibrated for flat response at their detents.
The Holman preamp is so well thought out that its precise bandlimiting not only prevents distortion in other components, it even worries about the other signals coming into the unit that aren't selected! Its internal wiring is shielded electrostatically with alternate grounded conductors, and the selector wafer switches use several decks and grounds to keep everything separated and without crosstalk. Unselected inputs are properly terminated, not left hanging as they are in most other preamps.
What goes on inside this preamp goes far beyond exotic preamps today, and even more importantly, what makes the Apt Holman Preamp sound so great is that it's designed to perfect the interfaces to and from all the other parts of a system. In other words, rapt attention has been paid in its design to ensure that signals coming to and from this preamp are well conditioned and matched to ensure sonic perfection from the entire system in the real world, not just on a test bench.
The name "Apt" comes from its definition as "an appropriate and intelligent solution to the task at hand." Newer preamplifiers today are mostly 25-pound billet aluminum cases filled with fluff: ordinary analog circuits controlled digitally with showy vacuum fluorescent displays, but missing many of the important control features and superior audio performance of the Holman Preamplifier. Instead of chasing idiotic things that consumers think are important but aren't, like what kind of wire's inside, the Apt Holman Preamplifier concentrates on what's far more important, like where those wires are connected and the analog circuitry around them.
Specificaties / Specifications
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