Preamplifiers — Audio Research LS-2

The LS-2 is an accomplished preamplifier from Audio Research, built around two 6H30 dual-triode tubes long respected in audiophile circles, running in pure class A with a cathode-follower topology that helps achieve low output impedance. The LS-2 brings Audio Research's most storied American engineering to a serious tube preamplification format with wide power-amplifier compatibility.

Key specs that matter

Two balanced and four single-ended analogue inputs are provided, with one balanced and one single-ended output. Gain is 12dBu, with input impedance at 25,000 ohms on both connections. Output impedance is a low 10 ohms balanced or 25 ohms single-ended - a figure the cathode-follower topology specifically delivers to ease matching with a wide range of power amplifiers. Frequency response spans 0Hz to 40,000Hz within plus-or-minus 3dB. Total harmonic distortion plus noise is 0.03%. At 482.6 x 177.8 x 444.5mm and 21.8kg, the LS-2 maintains a substantial tube-preamplifier chassis reflecting Audio Research's considered pure-class-A engineering.

Sound and use context

Expect the exceptionally rich, harmonically engaging character pure class A dual-triode tube amplification is broadly celebrated for, with the cathode-follower topology's low output impedance delivering easy matching with a wide range of power amplifiers.

Pairing

The low output impedance makes the LS-2 compatible with a wide range of power amplifiers, including those with comparatively demanding input-impedance requirements.

Alternatives

Audio Research's own broader preamplifier catalogue offers related alternatives at different price points within the same considered tube engineering philosophy.