The components I needed to choose for my first system were never in doubt: a turntable or record changer, an integrated amplifier, and a speaker. One of each, please, in those mono days.

Today, even in stereo, that trinity would be regarded as rather traditional—or, if you prefer, purist. Digital has exploded the range of source options and loudspeaker options. Yet amplifiers have not changed much in how and what they do.

The idea of using digital signal processing (DSP) to convert digital audio data sampled at 44.1kHz or 48kHz to a higher sample rate is not new. I first heard the beneficial effects of upsampling at Stereophile's 1998 hi-fi show in Los Angeles, where a pro-audio dCS 972 digital-to-digital processor was being used to convert 16-bit/44.1kHz CD data to a 24/192 datastream.