STAMP

Compact 20 W stereo power amplifier handcrafted in Germany — solid-core internal wiring and oversized toroidal transformer. The Stamp is Lehmannaudio's compact stereo power amplifier — a deceptively capable unit that delivers 2×20W into 4Ω from a chassis measuring just 280×115×42mm. Despite its small footprint, the Stamp is built with full audiophile integrity: fully solid-core internal wiring is soldered directly to sockets and PCB to eliminate plug connections, and the linear power supply is fed by a magnetically and statically shielded toroidal transformer with a 105µm copper layer on the PCB for low-loss current delivery. Frequency response runs from 12Hz to 20kHz (±1dB at 4Ω) with 20dB of gain. DIP switches enable bi-amp configuration using two Stamps. An optional mounting kit allows under-desk or on-wall installation. Best matched with loudspeakers of 87dB/1W sensitivity or higher. Weight: 1.9kg.

Technical background

The Stamp uses a Class D switching output stage — chosen for its power efficiency in a compact chassis — but pairs it with an oversized linear power supply featuring a shielded toroidal transformer. This eliminates the switching noise artefacts common to Class D amplifiers with switching PSUs, delivering the thermal efficiency of Class D with the sonic benefits of linear power. All internal wiring is solid-core copper, directly soldered without connectors.

Design story

The Stamp was designed in Cologne to fill the gap between Lehmann's headphone amplifiers and full integrated amplifiers — a compact power amplifier that treats desktop and near-field loudspeaker listeners with the same engineering seriousness as the headphone and phono product lines.

Best for

Audiophiles wanting a compact, high-efficiency power amplifier to partner Lehmann Audio preamps; those building a full Lehmann system with efficient speakers Desktop loudspeaker users; near-field monitoring enthusiasts; audiophiles with high-efficiency speakers wanting Lehmann quality in a compact power amplifier Desktop speaker amplification; near-field studio monitoring; compact second-system amplifier; pairing with Linear SE or Linear USB II as preamplifier

Awards & press

⭐ N/A "Huge, wide soundstage with resolved depth... keeps all its edginess and drive whilst walking the tightrope of listenability." — TNT Audio "The Stamp delivers far more than its modest dimensions suggest — a surprisingly musical and powerful little amplifier." — TNT Audio "Lehmann's Stamp is a compact powerhouse — the perfect desktop partner for high-efficiency loudspeakers." — SoundStage! Network