1. Microphone Types and Detection Key Points: Mainstream microphones on the market are divided into built-in microphones, USB microphones, 3.5mm microphones, condenser microphones, dynamic microphones, Bluetooth microphones, and lavalier microphones. Built-in microphones typically have lower sensitivity and are suitable for microphone sound tests; USB microphones are plug-and-play — during detection, confirm the device is correctly recognized; condenser microphones are highly sensitive and prone to clipping, requiring emphasis on clipping detection; dynamic microphones are relatively durable but may have weak high frequencies, making them suitable for frequency response evaluation through spectrum analysis. All types can be quickly confirmed through microphone sound test and recording test.
2. Levels and Gain Settings: Level (dBFS) represents signal strength. During normal speech, peaks should stably remain in the 70%–85% range, with averages between 30%–50%. By observing real-time levels through the microphone test tool, you can judge whether the gain is appropriate. If the volume bar stays at the top and shows "near overload," the input gain is too high and should be lowered to 60%–80%; if the volume bar stays below 20%, the gain is too low or the microphone is too far from your mouth. Proper gain setting is the foundation for clear recording.
3. Clipping and Distortion: Clipping occurs when the signal amplitude exceeds the digital upper limit and the waveform is flattened, manifesting as "cracking," "humming," or "hoarseness." This tool quantifies clipping by recording the time-domain waveform and counting the frequency of sample values touching ±1.0. If the rolling clipping rate exceeds 0.5%, the signal is clearly overloaded — we recommend lowering the gain or increasing the distance. Meanwhile, distortion detection can further distinguish whether it's digital clipping or distortion caused by the microphone's own nonlinearity.
4. Background Noise and Signal-to-Noise Ratio: Background noise is the noise level produced by the microphone and audio chain itself when there's no effective sound input, usually expressed in dBFS. In a quiet environment, the background noise of a healthy microphone is typically between -70 dBFS and -50 dBFS. Through signal-to-noise ratio testing, you can evaluate the gap between background noise and effective signal — an SNR of 40dB or above is considered excellent, while below 20dB means background noise is already seriously affecting vocal clarity. To reduce background noise, you can start by improving environmental noise, lowering input gain, and speaking closer to the microphone.
5. Frequency Response and Spectrum: A microphone's frequency response determines its sound "timbre." Through microphone spectrum analysis, you can display the frequency energy distribution in real time within the 20Hz–20kHz range, and calculate the energy proportion of five frequency bands. During normal speech, vocal energy is mainly concentrated in 100Hz–4kHz, and the spectrum should show a "peak" shape with high mid-frequencies and low ends. If there's almost no energy in the high-frequency band, the microphone has high-frequency loss; if the low-frequency band is abnormally prominent, it may be near-field effect or desktop vibration.
6. Daily Microphone Maintenance Recommendations: Regularly clean the microphone's pickup holes and pop filter, avoid liquid splashes, and use the microphone test tool to perform a monthly comprehensive microphone detection including microphone sound test, recording test, and spectrum analysis. This can effectively extend the microphone's lifespan. Once you notice abnormal pickup, low volume, or clipping, promptly test and consider adjusting gain, replacing the microphone, or cleaning the pickup holes.