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Does gain cause feedback?
In audio we talk about gain structure. It is how you use each stage of the signal path so you do not overdrive the output (Mains or monitors) and cause either distortion or feedback. Setting the gain structure properly will give you the headroom and lessen the probability of distortion and feedback.
What is gain in relation to feedback?
the gain of the amplifier is the ratio of output voltage Vo to the input voltage Vi. the feedback network extracts a voltage Vf = β Vo from the output Vo of the amplifier. This voltage is added for positive feedback and subtracted for negative feedback, from the signal voltage Vs.
Why is gain structure important?
Why is gain structure important? Proper gain structure is important because it affects signal-to-noise performance and available headroom within a sound system. Every sound system has some inherent noise, whether it be self-generated by the internal electronics or induced into the signal path by external sources.
What is the concept of gain structure?
The concept of gain structure is that, at each connection between components in the system, the signal level is as high as it can be (to minimize noise), but no higher than the maximum level that either component allows (so there is no distortion due to overload).
What is the formula for negative feedback gain?
Negative feedback amplifiers are designed so that the open loop gain A o (without feedback applied) of the amplifier is much greater than 1, and so the 1 in the formula becomes insignificant. The closed loop gain (A c) can therefore be approximated to:
How to describe voltage gain in negative feedback amplifier?
The voltage gain of any amplifier can be described by the formula: Because in the closed loop negative feedback amplifier (Fig. 3.1.2): the closed loop gain (A c) can also be described by the standard NFB formula:
What happens when peaks exceed the capacity of a gain stage?
As peaks exceed the capacity of a gain stage, the tops of the waveforms are clipped off, leading to distortion in the signal. Unexpected peaks are the primary cause of clipping in the preamp, but distortion is also common in intermediary gain stages, such as the EQ or dynamics processing.
Why is gain staging important in a sound system?
Said another way, proper gain staging allows your sound system to achieve the best signal-to-noise ratio. By attempting to reach the loudest peaks possible (without clipping) at each stage, you can achieve an ideal gain structure, but to do this, you need to consider each part of your system and understand the principles involved.