The Warm Audio WA-251 is a large-diaphragm tube condenser microphone designed to provide the tonal characteristics of classic 251 microphones for vocalists, musicians, and recording engineers in home, project, and commercial recording studios. Thanks to three polar patterns—cardioid, omnidirectional, and figure-8—selectable from the included external power supply, its versatility allows it to excel on anything from close-up vocals to distant room sounds. It handles SPLs up to 132 dB with low distortion and noise, and produces a frequency response of 20 Hz to 20 kHz.

The custom CK12-style capsule features brass construction and a gold-sputtered, 6-micron Mylar diaphragm with a single backplate. Tone-enhancing components, including a JJ 12AY7 vacuum tube, an American-made CineMag output transformer, and WIMA, Solen, and polystyrene capacitors, have been carefully selected to impart vintage-flavored tone characterized by a present high end and prominent low frequencies. Even the 7-pin cable, manufactured by Gotham Audio in Switzerland, rises to meet the demands of high-resolution audio production. It ensures the integrity of high frequencies and minimizes phase shift between the microphone and the power supply.

The WA-251 is supplied with a wood box and a shockmount, which reduces rumble and decouples it from problematic vibrations.