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Primare A35.2
Stereophile
|May 2020
POWER AMPLIFIER

My writing desk looks out over a large garden with chickens, bees, and feral cats. My chair sits only six feet from loudspeakers, playing softly on my left. Between the speakers sits whatever painting I am working on. That painting hangs no more than 10 feet from the oscilloscope and drill press in my kitchen. Best of all, my desk is only six feet from squadrons of ravenous sparrows attacking the suet cage on the fence outside my window. These real-world attractions keep my right and left brain in balance. Similarly, reviewing both analog and digital sources, as well as tube and solid-state amplifiers, keeps my review practice in balance. But not always. Sometimes my Apollonian self struggles to balance my Dionysian self. Especially when reviewing class-D amplifiers.
You see . . .
Class-D amplifiers are about quantities: like high power with high damping factors delivered at low temperatures in small, lightweight boxes at low dollars-per-watt prices. Class-D is a left-brain pleasure that declares, “Look what a smart shopper I am.”
Class-D lovers venerate Bruno Putzeys, the Belgian engineer who kick-started class-D’s current popularity, first with his UcD power amp module for Philips, and subsequently with his NCore amplifier modules and various switch-mode power supplies for Hypex.
I’ve been a forever fan of Bruno’s class-D modules be cause they deliver exceptionally clean, dynamic power at very reasonable prices. Best of all, Hypex makes these modules available, not only to other manufacturers (like Bel Canto, NAD, and MBL) but also as kits made available to DIY people. Looking at the bigger picture, it’s fair to say: Putzeys’s inventions are currently reshaping the landscape of high-fidelity audio.
This story is from the May 2020 edition of Stereophile.
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