Search results
Results From The WOW.Com Content Network
A voice-operated gain-adjusting device [7] or volume-operated gain-adjusting device [8] (vogad) is a type of AGC or compressor for microphone amplification. It is usually used in radio transmitters to prevent overmodulation and to reduce the dynamic range of the signal which allows increasing average transmitted power.
In live sound mixing, GBF is dependent on a wide variety of conditions: the pickup pattern (polar pattern) of the microphone, the frequency response of the microphone and of the rest of the sound system, the number of active microphones and loudspeakers, the acoustic conditions of the environment including reverberation and echo, and the relative positions of the microphones, the loudspeakers ...
This means that (1) moving the microphone closer to the sound source increases the signal level produced by the microphone, and (2) moving the microphone further away from undesirable noise sources will diminish the amount of noise in the microphone signal. Microphone placement is therefore an important aspect of gain staging [citation needed].
To maximize gain before feedback, the amount of sound energy that is fed back to the microphones must be reduced as much as is practical.As sound pressure falls off with 1/r with respect to the distance r in free space, or up to a distance known as reverberation distance in closed spaces (and the energy density with 1/r²), it is important to keep the microphones at a large enough distance ...
Here, the still-mic-level signal enters into a microphone preamplifier, which boosts the signal voltage to line level. For this example, the microphone preamplifier is built into a mixing board. It is typical for a mixing board to include a line trim after the preamplifier. This allows the amplitude of the now line-level signal to be adjusted.
Automixers balance multiple sound sources based on each source's level, quickly and dramatically adjusting the various signal levels automatically. [2] Automixers are used in live sound reinforcement to maintain a steady limit on the overall signal level of the microphones; if a public address system is set up so that one microphone will not feed back, then, in general, the automixer will ...
Another type of normalization is based on a measure of loudness, wherein the gain is changed to bring the average loudness to a target level. This average may be approximate, such as a simple measurement of average power (e.g. RMS), or more accurate, such as a measure that addresses human perception e.g. that defined by EBU R128 and offered by ReplayGain, Sound Check and GoldWave.
When the sound produced by the speakers is picked up by a microphone, it is further reamplified; this recirculation of sound can lead to "howling", requiring the sound technician to reduce the gain for that microphone, perhaps sacrificing the contribution of a singer's voice, for instance. Even at a slightly reduced gain, the feedback will ...