Rémi Guastavino the Director of Product Management at GRAS-Sound & Vibration joins to tell us about the use case and benefits of the new EQ 40PM. The GRAS EQ 40PM is a robust, cost-effective microphone designed for use in production line testing of loudspeakers and acoustic transducers. It has a wide frequency range, from 20 Hz to 20 kHz, and a dynamic range from 30 dB (A) to 120 dB. EQset incorporation in a microphone removes all of the traditional hassle associated with installing, setting up, and replacing microphones in a production line setting. EQset microphones all have flat response curves and fixed sensitivity. Sensitivity variation between individual microphones varies less than 0.2 dB from nominal sensitivity. The flat frequency response is less than 0.5 dB up to 10 kHz, another huge improvement over traditional production line microphones ±3 dB across the full frequency range. This provides a number of immediate benefits.

Cost efficiency—low microphone entry cost, no special hardware needed, and fully backward compatible with CCP setups.

Ease of use—a uniformly flat frequency response fixed sensitivity (or gain) for each EQset microphone makes EQ 40PM microphones plug and play in any 48 V phantom power or CCP-based setup.

Reduced risk—the extremely narrow pressure response spread (±0.5 dB) greatly reduces the risk of false passes and false failures, which greatly reduces the risk of bad units reaching the customer and the risk of good units being scrapped or recycled.

High environmental stability—the unique design of the EQ 40PM provides this range of microphones with unmatched environmental stability. Deviation on a typical production line is less than ±0.3 dB, so there is no need for corrections due to temperature or humidity.