Gold-Plated Copper (Contact Surface, Not Conductor)

Gold plating on a copper or brass connector contact surface (typically 1–3 μm thickness). Not used as a bulk conductor — gold’s IACS is only ~70% — but as a corrosion-resistant contact surface on plugs, jacks and binding posts.

The benefit is mechanical-electrical rather than audiophile: gold doesn’t oxidize, so contact resistance stays stable for decades. The audible benefit is preserved performance over time, not improved performance on day one.

Standard plating on the contact surfaces of every premium audio connector — 4.4 mm Pentaconn, XLR4, RCA and others. Higher tiers use 24K gold over a nickel intermediate layer.