ARCHITECT'S and ENGINEER'S SPECIFICATION

The microphone shall be of the electret condenser type. It shall operate into an impedance of 150 ohms, and have an output at 1 Pa of -45 dBm. It shall have cardioid directional response, and a band-width of 40 Hz to 18 kHz, with a bass enhancement by proximity effect when used within 4" (10.2 cm) of the sound source, and a bass reduction when placed 24" (61 cm) or farther away from the sound source. It shall have a dynamic range of 119 dB, and be capable of accepting signals up to 141 dB-SPL (re: 20 µPa) with 1%) THD or less. The microphone shall be pro-vided from the preamplifier with phantom power of [18 to 50 Vdc], or an in-line power supply shall be provided. The case shall be manufactured of machined steel and finished in fawn beige micromatte. The overall length of the micro-phone shall be 6.94" (17.6 cm), and the maximum diameter shall be 1.06" (2.7 cm), while the shank diameter shall be 0.75" (1.9 cm). -
The microphone shall be the Altec Lansing model C649.