The Endevco array microphone model EM40PH 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 135 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 EM40PH requires a constantcurrent power supply, eg. model 4416B. Close manufacturing tolerances together with the advantages of the TEDS chip, provide the model EM40PH with a high degree of interchangeability; a major advantage when used in multiples forming arrays and matrices. The low cost of the model EM40PH is a key consideration when setting up measurements requiring a multiplicity of concurrent transient and spatial data. Calibrating the model EM40PH with an Endevco pistonphone, e.g. the 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 EM40PH High-sensitivity array microphone Description 1 Transducer Electronic Data Sheet - as proposed by IEEE-P1451.4 cmyk

Endevco® model EM40PH High-sensitivity array microphone Specifications Nominal sensitivity: at 250 Hz 50 mV/Pa (±2 dB) Frequency response (re. 250 Hz): ±3 dB 10 Hz–100 Hz ±1 dB 100 Hz–3 kHz ±2 dB 3 kHz–10 kHz ±3 dB 10 kHz–20 kHz Upper limit of Dynamic range: Max. ouput 135 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 socket Length: 60.0 mm (2.36 inches)...