The Endevco array microphone model EM40PL is a low-cost microphone for general purpose measurements in arrays and matrices. It has a wide useful frequency range reaching up to 20 kHz (Fig.1) and a large dynamic range topping at around 150 dB. It has an integrated Isotron® preamplifier and is delivered with a built-in TEDS1 chip which enables it to be programmed as a complete unit. The model EM40PL requires a constant-current power supply, eg. model 4416B. Close manufacturing tolerances together with the advantages of the TEDS chip provide the model EM40PL with a high degree of interchangeability; a major advantage when used in multiples forming arrays and matrices. The low cost of the model EM40PL is a key consideration when setting up measurements requiring a multiplicity of concurrent transient and spatial data. Calibrating the model EM40PL with a Endevco pistonphone, model EM42AA is as straight-forward as calibrating any other Endevco ¼-inch microphone. All Endevco microphones are individually checked and calibrated before leaving the factory. An individual calibration chart is supplied with each microphone. Applications • Multi-channel measurements • Sound-field analyses • Sound-power measurements • Concurrent spatial and transient measurements Endevco® model EM40PL Array microphone Description 1 Transducer Electronic Data Sheet - as proposed by IEEE-P1451.4 cmyk

Endevco® model EM40PL Array microphone Specifications Values quoted for 23°C and 4 mA supply Nominal sensitivity: at 250 Hz 10 mV/Pa ±3dB Frequency response (re. 250 Hz): ±3 dB 10 Hz–100 Hz ±1 dB 100 Hz–3 kHz ±2 dB 100 Hz–10 kHz ±3 dB 10 kHz–20 kHz Upper limit of Dynamic range: Max. without clipping 150 dB re. 20 ìPa Lower limit of Dynamic range: Thermal noise < 32 dBA re. 20 ìPa Phase match: 100 Hz to 3 kHz ± 3° 3 kHz to 5 kHz ± 5° Influence of axial vibration: for 1 m/s2 50 dB re. 20 ìPa Temperature range: -10°C to +50 °C (14°F to 122°F) Output impedance: < 50 Ù Output connector: SMB coaxial...