Recording Handbook - Hol.gr

The concept is simple, the execution can be complicated. The most important thing to remember is what
kind of code you've got. Keep good notes! BACK TO INDEX
3. The Sound Source
There are only two ways to get your sonic information onto the tape, through a microphone or directly
from an electronic output. In general, the quality of what comes back is affected by the quality of the
equipment the signal passes through.
a. Voices, Horns and Acoustic Piano
While the human voice is the most dynamic, all of these instruments present a similar problem to the
engineer. How can we preserve the performance, that is the soft and loud of it, and get it accurately on
tape? With these instruments, we usually have to use a microphone.
The two main types of microphones are "dynamic", which have no active electronics involved in
amplifying the input signal, and "condenser", which require either batteries or "phantom power" to power
their electronics. Both types have a thin membrane, called the diaphragm, that vibrates and that physical
vibration is translated into an electronic signal. In general, condenser mikes are brighter and have a
broader frequency response, but they are more fragile. That's why you usually see an SM57, a general
purpose dynamic mike, in the lead singer's hands at a concert. They can withstand a lot of abuse.
Classic condenser microphones like the Neumann U-47 and AKG C-12 use vacuum tube electronics and
are treasured for their unique sound. They are rather large and have diaphragms 2 inches in diameter.
Ribbon microphones are another vintage design that incorporates a thin rectangular strip as it's diaphragm,
hence the name. PZM designs are a relatively new invention. They work on a completely different
principle and don't look anything like traditional microphones.
The signal created by the microphone is very small and it is the microphone pre-amp that increases this
level to what is known as "line-level" for interfacing with the mixing board. This is yet another link in the
chain with it's opportunity to affect the sound, and they do.
Everyone has their favorite microphones and pre-amps for different situations and most do color the
sound. The important thing is whether you like that color and if it's appropriate for the particular situation
at hand. Here again, we run into the concept of "flat frequency response" and again it is relatively
meaningless. Most microphones are not "flat" and some are better suited for certain jobs than others. As
always, you need a reference and in this regard, frequency response charts and the like can be useful.
Rules are made to be broken.
Signal processing is another powerful weapon for your sonic arsenal. The judicious use of compression
can be a big help in lots of situations. Compressors were originally developed to compensate for the
limited dynamic range of analog tape. Basically, they make the soft parts a little louder and the loud parts
a little softer. This performs the dual function of keeping the soft passages higher above the "noise floor"
and preventing the loud parts from getting too loud and peaking into distortion. Most compressors allow
you to change the "range" (1:1, 2:1, 4:1, etc.) and the "attack time" and "release time" of the effect.
Expanders and Limiters are related to compressors. Expanders make the soft parts softer and the loud parts
louder. Like compressors, you can set the range, and attack and release times of the effect. With limiters
you can set a threshold that cannot be exceeded. Noise Gates simply do what their name implies by
shutting off the signal path when there is no input.
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