Cables And Connectors; Microphones - Avalon VT-737SP Operation Manual

Basics

6.3 Cables and Connectors

Regardless of how high the quality of your
mics, mixing console, singal processors,
recording devices and monitors, the entire
system can be degraded or silenced by a bad
cable. Hum, crackles and lost signal due to
open circuits, or failed outputs due to shorted
circuits can be caused by cable problems. You
should never try to save money by cutting
corners with cables or connectors.
High price alone does not guarantee a good
product. There are major differences between
similar looking cables. All wire is not the same,
nor are all look-alike connectors made the
same way. Even if the overall diameter, wire
gauge and general construction are similar,
two cables may have significantly different
electrical and physical properties. Resistance
and capacitance between conductors, induc-
tance, overall flexibility, shielding density,
durability, ability to withstand crushing or
sharp bends, tensile strength and other factors
can vary greatly. More stands usually yield
better flexibility and less chance of metal
fatigue or failure caused by an inadverten nick
in the cable.
Connectors also can differ dramatically. They
must be well made, with low contact resis-
tance. They should be well secured to the
cable, with thoroughly soldered shields and
inner conductors plus good strain relief. It is
important to routinely check your cables and
connectors for broken or nearly broken con-
nections.

6.4 Microphones

Microphone is a generic term that is used to
refer to any element which transforms
Avalon Vt-737sp Operation Manual
accoustic energy
energy (the audio signal). Microphone selec-
tion and placement during recording is one of
the single most important skills a recording
engineer can learn. There are generally three
main types of microphones used in recording:
Dynamic, Condenser and Ribbon micro-
phones.
A Dynamic microphone is made up of a flexi-
bly mounted diaphragm coupled to a coil of
fine wire, with a voice coil mounted in the air
gap of a magnet.
When sound strikes the diaphragm, the
diaphragm surface vibrates in response. The
motion of the diaphragm couples directly to
the coil, which moves back and forth in the
field of the magnet. As the coil cuts through
the lines of magnetic force in the gap, a small
electrical current is induced into the wire. The
magnitude and direction of that current is
directly related to the motion of the coil, and
thus is an electrical represensation of the inci-
dent sound wave.
Dynamic microphones are not only highly
dependable, they are also extremely rugged.
For this reason, they are very good for record-
ing loud instruments such as drums and elec-
tric guitars. Two of the most common dynamic
mics used for recording are the Shure SM57
and the Sennheiser 421.
The Condenser microphone is made of a
gold-coated plastic diaphragm that is mount-
ed above a conductive gold plated ceramic
back plate. The diaphragm and back plate,
separated by a small volume of air, form an
electrical component called a capacitor (also
known as a condenser).
(sound) into electrical
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