Measurement microphone 4938

externally-polarizedwith built-in TEDS preamplifierfor high temperatures

Overview
1/4-inch pressure-field microphone Type 4938, designed for high-frequency and high sound-pressure-level measurements in demanding environments. Available with passive output and TEDS for automatic identification.

Key features

• Pressure-field (1/4-inch) transducer
• Frequency range typically 4 Hz to 70 kHz (model dependent)
• Optimized for high-frequency and high-level measurements (max SPL up to ~172 dB, model dependent)
• Passive output; common sensitivities 1.4 mV/Pa or 1.6 mV/Pa
• Side-venting for flush mounting options
• TEDS enabled for automatic reading of model, serial number and sensitivity
• Availability of high-temperature variants (some models up to 300 °C)

Applications

• Precision acoustic testing at high frequencies
• Measurements of high sound pressure levels in test cells and field environments
• Laboratory and on-site acoustic characterization under extreme conditions

Kit contents

• Microphone Type 4938 (microphone capsule)
• Optional preamplifier Type 2669-L (depending on kit)
• Unit assembled and sealed as a single serial-numbered device in cleanroom

Technical specifications

• Model designation: Type 4938
• Family: Family 4938
• Standard: IEC 61094 (pressure-field)
• Polarization: classical/external polarization
• Frequency range: ~4 Hz to 70 kHz (model dependent)
• Sensitivity: ~1.4 mV/Pa or ~1.6 mV/Pa (model dependent)
• Dynamic range: typical maximum SPL up to ~172 dB; minimum measurable level depends on model
• Output: passive
• Venting: side venting
• Assembly: cleanroom assembled and sealed; includes TEDS
• Brand: HBK