Description

When you’re pulling an RTA trace, correcting a room, or verifying a system’s frequency response, you need a microphone that tells the truth. The Earthworks M23 was engineered exactly for that job — a free-field measurement mic with a flat, wideband response and a fast impulse capture that avoids smearing transients or coloring the signal you’re trying to measure.

Flat frequency response from 9Hz to 23kHz (±1/-3dB)
Omnidirectional polar pattern with consistent off-axis behavior
Meets or exceeds ANSI Type 1 and applicable IEC 61094 requirements
Stable across a wide temperature and atmospheric range, so readings stay repeatable job after job

This is the same lineage of mic recognized in the industry as an evolved take on the SMAARTMIC formerly sold by EAW, and it’s compatible with the measurement platforms you’re probably already running — SMAART, MLSSA, Spectrafoo, TEF, and RTA software, plus systems from dbx and DEQX.

Sensitivity: 30mV/Pa (-30.5dBV/Pa)
Max acoustic input: 142dB SPL
Noise floor: 22dB SPL equivalent (A-weighted)
Output: XLR, pin 2+, 100Ω balanced
Requires 48V phantom power, 10mA
Dimensions: 165mm x 22mm (6.5 x 0.86 in), weight 160g (.35 lb)

Every M23 ships with its own individual calibration chart documenting open-circuit sensitivity and frequency response, so you know exactly what you’re working with before it ever hits a stand. An electronic calibration file is also available. Operating range runs -10°C to +40°C, storage -20°C to +50°C, and Earthworks recommends re-calibration every five years to keep your measurements honest.

For engineers who need consistent, trustworthy data rather than a mic that just sounds good, the M23 earns its place in the measurement kit.