1, impedance matching
When using a microphone, the output impedance of the microphone is the same as the input impedance of the amplifier. If the mismatch ratio is above 3:1, the transmission effect will be affected. For example, when a 50Ω microphone is connected to an amplifier with an input impedance of 150Ω, although the output can be increased by nearly 7Db, the sound of high and low frequencies will be significantly lost.
2, the connection line
The output voltage of the microphone is very low. In order to avoid loss and interference, the connection line must be as short as possible. The high-quality microphone should be a double-core stranded metal shielded wire. Generally, the microphone can be a single-core metal shielded wire. The length of the high-impedance microphone transmission line should not exceed 5 meters, otherwise the treble will be significantly lost. The connection of the low-impedance microphone can be extended to 30m–50m.
3. Working distance and near-talk effect
Generally, the working distance between the microphone and the mouth is 750px–1000px. If the distance is too far, the reverberation increases and the noise increases relatively. If the working distance is too close, the signal will be distorted due to excessive signal, and the low frequency sound will be too heavy to affect the language. The clarity. This is because the directional microphone has a "near-talk effect", that is, the low-frequency sound is significantly improved when broadcasted at close range. However, sometimes the singer intends to use the "near talk effect" to make the singing effect more beautiful and beautiful.
4, the angle between the sound source and the microphone
Each microphone has its effective angle. The general sound source should be aligned with the microphone center line. The larger the off angle between the two, the higher the treble loss. Sometimes when using a microphone, it has a "long" sound, and when the microphone is deflected by some angle, it can be lightened.