D
IGITAL
R
ECOR DING
With your microphones in place, you’re ready to begin recording to disk.
Double-check the input and output settings in your software first. On Mac
OS X, look for preferences under the application menu (the menu with the
name of the program, like Audacity or Live), and on Windows select File >
Preferences. You can then proceed to record.
Setting Levels
With an input enabled, you’ll need to make sure you have the right input
level. If the signal is too weak, the recording will be too quiet, and amplifying
it to an audible level will add noise. If the signal is too strong or “hot,” it can
cause distortion. By setting your input gain so that the level saturates your
dynamic range without distorting, you’ll get the cleanest possible recording.
This means you need to watch your meters while you’re recording and
make appropriate adjustments as needed (Figure 6.23).
Headroom
Every device has a dynamic range (the amplitudes it can accommodate from
minimum to maximum). On analog equipment, there’s an additional range
above the maximum recommended level (labeled on a meter as 0 dB), up
to the level at which signal significantly distorts or clips. This range is often
colored red on equipment meters. If you’ve ever gone “into the red,”
you’ve exploited the additional range, which is called dynamic headroom
(Figure 6.24).
On analog equipment, you’ll want your meters to read approximately 0 dB
as often as they can, with an occasional excursion slightly “into the red.”
Meters on analog equipment can show a little bit of clipping when the sig-
nal isn’t actually significantly distorting. Digital equipment works differently:
because amplitude is stored as a number and not as a continuous voltage, its
Get the right levels:
Analog:
0 dB, or a little
more or less
Digital:
Approaching
but never crossing 0 dB
Figure 6.23 Watch your
meters (left) to set the right
level. If you need to, adjust
input gain in your hardware
or software, as shown here in
Audacity (right).
For more informa-
tion, see:
Chapters 3–4:
Connect
and configure your
equipment
Chapter 7:
Add signal
processing to sweeten
your sound or add com-
pression and effects
Chapter 10:
Mix sources
together and edit and
arrange your sound
Chapter 13:
Record
on the fly during a
performance
187
D
IGITAL
R
ECORDING
maximum is really its maximum. Generally speaking, digital equipment
doesn’t have any dynamic headroom; therefore, you’ll have to set your
inputs so that your levels get near the 0 dB threshold without crossing it.
Distortion
“But wait,” you may be saying, “I love distortion!” Odds are, you like ana-
log distortion, a “fuzzy,” warm sound generated by analog equipment
pushed just past its headroom. From distortion pedals to “overdriving”
recorded tracks, musicians have long made use of slight overdrive (pushing a
device just past its amplitude maximum) to get a desired effect.
Digital devices distort differently: instead of rounding off the top of a wave-
form as it passes beyond the amplitude maximum, they slice off the tops of
the sound waves, creating a straight line (Figure 6.25). This result is called
digital clipping, and it’s almost never desirable. In fact, if you want to achieve
analog-style distortion, you’ll need software that can emulate the result.
(See Chapter 7 for more on this effect.) Unless you want the specific and
unpleasant sound of digital clipping, make sure your digital meter never
headroom
0 dB
Figure 6.24 Analog signal
(left) has additional headroom
beyond 0 dB, but anything
above 0 dB on a digital meter
(right) will result in digital
clipping.
188
C
HAPTER
6: R
ECORDING
I
NSTRUMENTS AND
S
OUND

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