Click here to purchase the entire book in PDF format. Gain Management From the time the sound arrives at the diaphragm of your microphone to the time the signal gets recorded, it has to travel a very perilous journey, usually through a lot of wire and components that degrade the quality of the signal every step of the way. One of the best ways to minimize this degradation is to ensure that you have an optimal gain structure throughout your recording chain, taking into account the noise and distortion charactersitics of each component in the signal path. This sounds like a monumental task, but it really hinges on a couple of very simple concepts. The first basic rule (that you'll frequently have to break but you'd better have a good reason...) is that you should make the signal as loud as you can as soon as you can. For example, consider the example of a microphone connected through a mic preamp into a DAT machine. We know that, in order to get the best quality digital conversion of the signal, its maximum should be just under 0 dB FS. Let's say that, for the particular microphone and program material, you'll need 40 dB of gain to get the signal up to that level at the DAT machine. You could apply that gain at the mic preamp or the analog input of the DAT recorder. Which is better? If possible, it's best to get all of the gain at the mic preamp. Why? Consider that each piece of equipment adds noise to the signal. Therefore, if we add the gain after the mic preamp, then we're applying that gain to the signal and the noise of the microphone preamp. If we add the gain at the input stage of the mic preamp, then its inherent noise is not amplified. For example, consider the following equations: