HARMAN KARDON HK680i DIGITAL QUARTS RECEIVER ORIGINAL TECHNICAL SERVICE MANUAL | eBay
HK680i and EQ8 ——-Paid $9.99 each! Its usually $4.99 at our local goodwill today, but still i cant complain!! Everything works and sounds awesome. Did not do any cleaning or anything yet.
Harman Kardon HK-680i Stereo Receiver Photo #2249267 - US Audio Mart
Harman Kardon, HK-680i Digital Synthesized Stereo Receiver -SOLD – Holt Hill Audio
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Harman kardon 680i verses Pioneer SX980 — Polk Audio Forum