9mm Electret Microphone Capsule for Respirator Mask

Electret Microphone Capsule for Respirator Mask 9mm

The ECM-EM212U-51 is a 9.7 × 9 mm unidirectional microphone capsule with a sensitivity of -51dB±2 and a signal-to-noise ratio of 62dB. It is designed for use in respirator masks.

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Minimum order quantities (MOQs) apply.
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🧪 Sample

Free (std. models) + shipping

🧭 Trial Order

From 200 pcs (1st order only)

📦 MOQ

5,000 pcs (mixed models allowed)

Model: ECM-EM212U-51
Dimensions: 9.7 × 9 mm
Directivity: Unidirectional
Sensitivity: -51 dB ± 2
Impedance: 2.2 kΩ
S/N Ratio: 62 dB
Max SPL: 115 dB
Operating Voltage: 2 Vdc
Frequency Response: 100 Hz ~ 10 kHz

Tags: 9.7mm Electret Equipment Mics Solder Pads Electret

Technical Specifications

Our 9790 noise-canceling microphone head features a Panasonic JFET and a perforated housing design. The cardioid directional mic effectively reduces wind noise.

Standard Test Circuit

ECM-EM212U Test Circuit: 2.2kΩ bias, 2V supply, 1μF output

2.2kΩ bias resistor, 2V DC supply, 1μF output capacitor. Standard configuration for voice frequency measurement.

Typical Frequency Response

ECM-EM212U Frequency Response: 100Hz-8kHz rise with peak at 8kHz, then attenuation to 12kHz

Frequency response rises progressively from 100Hz to 8kHz, reaching a peak at 8kHz, followed by a gradual roll-off up to 12kHz, optimizing voice clarity.

Dimensions (Unit: mm)

ECM-EM212U Dimensions: Φ9.7×9.0mm capsule with side vent holes and front dust mesh

Compact Φ9.7×9.0mm microphone capsule featuring a front dust mesh for protection, and several small vent holes evenly distributed around the side perimeter for acoustic balance and performance. The back side is sealed without openings, ensuring durability and environmental resistance.

Packaging Overview

Standard packaging: 100 pcs per small box.
10 small boxes (1,000 pcs) are combined into one medium carton.
Several medium cartons are further packed into a large outer carton.
Pin-type microphones are protected with foam inside the small box.
Other types are packed directly or sealed in anti-static bags.

Reliability Tests

High Temperature Test: Microphone subjected to +80℃ for 100 hours, followed by 3 hours at room temperature.

Low Temperature Test: Microphone subjected to -40℃ for 100 hours, followed by 3 hours at room temperature.

Humidity & Heat Test: Microphone exposed to +55℃ and 85% relative humidity for 100 hours, followed by 3 hours at room temperature.

Thermal Shocking Test: Microphone subjected to [+80℃ 0.5H → room temp 1H → -40℃ 0.5H → room temp 1H] for 10 cycles, then exposed to room temperature for 3 hours.

Vibration Test: Microphone subjected to two hours of vibration in x, y, and z directions with frequencies of 10-55Hz and a 1.52mm amplitude.

Drop Test: Microphone dropped 5 times from a height of 1.0 meter onto a slippery marble floor, without packaging, and still performs normally.

Storage and Operating Temperature Range: Suitable for environments ranging from -35℃ to +60℃.

Sampling Process

Confirm customer requirements:

Review product application, microphone capsule specifications, usage scenarios, and sound quality needs.

Recommend and specify:

Provide recommended microphone capsule models and detailed specifications for customer evaluation.

Sample provision and testing:

Deliver microphone samples for customer testing and feedback purposes.

Optimize and finalize:

Refine microphone design based on feedback, finalize samples, and proceed to mass production upon quality approval.

Quality Assurance

Conducting sampling inspections of incoming materials to ensure compliance with standard requirements.

Performing inspection audits to ensure the stability and control of the entire manufacturing process.

Conducting pre-shipment inspections to ensure that products meet established quality standards.

Acoustic Laboratory

Testing of background noise, sensitivity, frequency response curve, and directionality indicators.

Verification of the impact of different circuits, structural dimensions, materials, and processes on indicators.

Reliability testing at both the new product design stage and the mass production regular stage.

Automatic Workshop

Utilizing fully automated production lines to ensure high efficiency and consistency.

Equipped with state-of-the-art facilities, including a 10,000-level dust-free workshop.

Employing a rigorous 21-step process to guarantee product stability.