Harman Kardon PM660

At the time (1983–1985), Harman Kardon claimed the PM660 was designed to be the ultimate integrated amplifier, and I must say its smooth, crisp sound truly impressed me. It’s a very muscular 80-watt amplifier, with no shortage of power or clarity.

Like other HK components, its power rating is deceptively conservative. It can deliver a steady 80 pure watts into 8 ohms, hour after hour. But when the music demands more, the PM660’s design has plenty of reserve power.

It features four rows of black anodized Sharfin heatsinks and a properly isolated phono stage, complete with an MM/MC selection switch and a four-way capacitance adjustment for the MM phono input. Robust, reliable, and very powerful.

In terms of features, the PM660 has everything an audiophile could want: variable intensity bypass, support for two cassette decks and two pairs of speakers, plus high and low filters. It also includes two-way cassette copying, audio muting, tone correction, and a mono/stereo/stereo-reverse switch.

Additionally, a Tape Out selector lets you record from one source—like your tuner—while listening to another, such as your turntable.

For critical listening, the PM660 offers a Main Direct switch, which routes the audio signal directly from the Function Select switch to the power amplifier. This completely bypasses balancing, tone controls, mode, and filter circuitry, providing the simplest possible signal path for maximum fidelity.

A small but thoughtful detail: instead of switching the speakers on abruptly with a relay “click,” the PM660 introduces sound with a smooth fade-in lasting just a fraction of a second. It’s a minor touch, but it shows how Harman Kardon paid as much attention to detail as they did to fundamentals.

Despite its understated appearance to audiophiles, the PM660 is unquestionably a great-value integrated amplifier—by any standard.