The Mechanics of Recording
There's a great deal more to recording than setting up a microphone and plugging it into a tape recorder. These days it's as much science as art.
Live Or Overdub?Ensembles of every kind are used to playing together live, whether it's performing in public or simply rehearsing. There's a feeling that comes from a performance that can't be duplicated. That's one reason many bands opt to record at least the basics of a track live in the studio (it's also quicker and therefore cheaper than building tracks).
However, that presents its own problems. There has to be separation of the sound of the instruments - in other words, you don't want the drum sounds to be audible through a microphone used to record the guitar, for example. In some cases, at least with rock bands, the amplifiers will be in a different room to the musicians. With acoustic instruments, the players might sit in isolation booths, able to see each other, but only hear the others through headphones.
Building a track by recording the instruments separately became a standard studio technique for rock and pop music. It allows for greater clarity and manipulation of the individual parts, and possibly greater precision. But the musicians have to know the pieces by absolute heart, and be able to work through them alone. Generally, this overdub method doesn't have the same soul as something recorded live.
Recording The InstrumentsWith a few exceptions, most instruments are amplified these days. Even the acoustic guitar usually has a transducer for live performance, which is fed into a P.A. system. In the studio, though, you have choices about how to record. You can use "direct injection," by which the instrument is fed directly into the control desk without using an amplifier, or you can use a microphone on the speakers (there's also a direct out from the amplifier to the desk). As amplifier settings (and indeed the amplifiers themselves) can affect the sound of an instrument, think carefully before you make your choice (of course, there are foot pedals that replicate the sound of different amplifiers). There are pros and cons to both choices, the biggest disadvantage being the time it takes to get the sound using a microphone.
A drum kit takes up a lot of microphones and tracks (the same is true with several percussion instruments). The general positioning of the microphones is quick, but from there obtaining the best drum sounds is a tedious procedure, with the drummer hitting each drum time after time as the engineer fiddles with the controls. However, the result can justify the amount of time spent.
Strings and brass can be both easier and harder. For small ensembles it's quite easy to rig up microphones capturing not only each instrument but also the overall sound (a hanging mic). Orchestras requite special ability and training on the part of engineers. The sheer volume of brass instruments means that microphones can't be placed as close, for instance.
Recording VocalsAlmost invariably, the vocal tracks will be recorded after the instrumental tracks. This not only allows the singer to fully hear the instruments through headphones, but also to have a greater sense of control. Some studios will have specific vocal booths to help the engineer manipulate the sound. It's important, too, for the singer to hear him or herself, to judge their pitch and make sure they don't go flat or sharp.
But hitting the right notes is only one half of the recording. The other is getting a convincing performance. It has to sound passionate, as if the singer has put his whole heart into it. That takes time - but it becomes a fine balance. If there are too many takes the voice begins to suffer and doesn't sound as good.
You'll find the recording process full of tedium, broken by brief moments of excitement. But the end result more than makes up for all the time spent sitting around.