The ECM-999 is an omni-directional test and recording microphone with a 1/4" inch pre-polarized condenser capsule. An extremely affordable alternative to measurement and calibration microphones costing many times more, the ECM-999 is being packaged with many of today's popular room analysis systems. The ECM-999, with its excellent sonic characteristics and smooth accurate response form 20 Hz-19 kHz, is also suited for miking group vocals, choirs, pianos, drum overhead, and room ambience. Output impendance: 200 Ohm. Power requirements: 9 ~ 52 V. Maximum sound level: 128 dB.