Harman-Kardon HK 770

Price trend

Sold or Listed Prices

7 market transactions via web search — not HiFi Registry sales.

Understanding the market

Half of recorded transactions fall between $275 and $500. The full range runs 3.0× from lowest to highest, which is normal for used equipment where condition, included accessories, and service history vary between units.

What buyers should know

Confirm both monoblocks have matching service histories — a pair where only one has been serviced is effectively two different amplifiers. Check that the seller has both original cartons; these are heavy and awkward to ship safely.

This range reflects 7 recorded sales, compiled from publicly listed and completed sales elsewhere on the used market, not from HiFi Registry transactions. That is enough to establish a working range, but not enough to be precise — treat it as a guide rather than an appraisal.