PreparationA typical session in a modern audio recording studio will, with some variation, follow a basic procedure. The recording engineer, calling upon his or her knowledge and experience, will place microphones strategically to pick up sound sources, and if necessary will place absorbent baffles between microphones to reduce leakage (i.e. extraneous sound picked up by a microphone from other nearby sources), thus improving isolation of the sources in the microphone signals.
The microphone output signals, and those of inline sources, are fed by cables to discrete input channels of the mixing console, also known as a board, a desk, or a mixer. With these links the signal chain begins. Each of the input channels of the mixing console is hard-wired with various controls for adjusting the tonal quality, input gain, and output volume of a signal. In addition, signals can be routed independently from each channel, via auxilliary sends, to side-chain circuits, which may include other signal processing devices such as compressors or reverberation units. The outputs of these devices are then fed to discrete auxilliary returns, so that these signals, too, may be treated independently.
Basic TracksOnce the engineer, musicians, producer, and anyone else who may have a say in the matter are comfortable with their preparations, the session may proceed in earnest. As the musicians perform, the sound is of course being recorded. Most often, the output signal of each channel of the mixing console will be routed directly to a discrete track of a multitrack tape, in order that it may be treated independently in the subsequent mixdown to a two-track master. On occasion, groups of channel outputs will be routed together via bus to one or more tape tracks, either for easier handling, or to conserve the limited number of available tracks.
OverdubsOnce the basic tracks have been recorded, it is common practice to overdub; that is, to add elements to the existing recording. For an overdub, a musician will monitor, through a headset, a mix of the basic tracks on tape, while he or she performs the part to be added. The new part is recorded to an available track on the same piece of tape.
MixdownAfter all the parts to be used in the recording have been printed to tape, the engineer plays back the recording for review. The output signal from each track on the tape is routed to an input channel of the mixing console, and adjustments are made to various aspects of each signal, until the resulting sound is satisfactory to all concerned. The tape is then played through from beginning to end, while a two-channel mix of the tracks is sent from the console to a two-track tape recorder, which records the mix. The two-track tape will ultimately serve as the master from which all other masters and, in turn, products for distribution, will be made.