Electret microphone capsules offer advantages like high sensitivity, small size, and low power consumption. However, there are specific standards and guidelines for selecting the appropriate sensitivity for your application. Without a clear understanding of the usage scenario, engineers might face inefficiencies and repeated experiments during the design process.
Below are some guidelines for choosing the sensitivity of electret microphone capsules, which can serve as a reference. Ultimately, the product's testing results should be the deciding factor.
1. Amplifier Gain
The first step is to confirm the gain of your product's amplifier. If the amplifier gain is high, a microphone with lower sensitivity can be selected. For example, Bluetooth amplifiers generally have high gain, so microphones with around -40dB sensitivity should suffice.
2. Sound-Controlled Toys
For sound-controlled toys, which don't have strict sensitivity requirements, a microphone with around -35dB sensitivity is recommended.
3. Microphone Arrays
For microphone arrays, consistency is critical, so microphones with a sensitivity error of less than 2dB are ideal.
4. Karaoke Microphones
To avoid feedback, a microphone with medium sensitivity (around -40dB) is recommended for karaoke microphones.
5. Voice-Controlled Lights
For voice-controlled lights, only sensitivity matters, and frequency response and distortion are not as important. A microphone with sensitivity greater than -30dB should work well.
6. Voice Control
For voice-controlled applications, a microphone with moderate to high sensitivity is preferred. A microphone that is too sensitive can cause noise triggers and incorrect activations.
7. Audio Recorders
For audio recorders, where amplifier gain is generally low, microphones with higher sensitivity (e.g., above -30dB) should be used.
8. Surveillance Products
Surveillance products require even higher sensitivity. For long-distance and high-altitude sound capture, microphones with ultra-high sensitivity (around -26dB) are recommended to ensure clear audio collection.
