4mm Electret Microphone Insert for Lavalier Mics

Electret Microphone Insert for Lavalier Mics 4mm

The ECM-B4015UL-30 is a 4 × 1.5 mm unidirectional microphone capsule, with a sensitivity of -30dB±2 and a signal-to-noise ratio of 60dB. It is suitable for close-range applications requiring directional sound capture.

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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-B4015UL-30
Dimensions: 4 × 1.5 mm
Directivity: Unidirectional
Sensitivity: -30dB±2
Impedance: 2.2KΩ
S/N Ratio: 60dB
Max SPL: 100dB
Operating Voltage: 3Vdc
Frequency Response: 100Hz~16KHz

Tags: 4mm Electret Conference Mics Solder Pads Electret

Technical Specifications

Our 4mm high-sensitivity lapel microphone head, equipped with a unidirectional electret interference-resistant mic core, features the 4015 transducer. Using Korean RF JFET, it contains three capacitors to shield RF interference, effectively ensuring stable and reliable performance.

Standard Test Circuit

Test conditions: RL = 2.2kΩ, Vs = 2V, C = 1μF

Typical Frequency Response

Frequency response covers 100Hz to 16kHz. It rises steadily from 100Hz to around 1kHz, remains relatively flat between 1kHz and 3kHz, then gradually climbs again before beginning to roll off near 8kHz.

Dimensions (UNIT: mm)

Appearance Dimension

Capsule measures 4mm in diameter and 1.5mm in height. The front is equipped with a dustproof mesh, and the rear features an acoustic port.

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.