Pitch correction has become widespread in commercial studio recordings,
which has also made it controversial. It is possible to overuse automatic
pitch correction, which has added to complaints about modern pop songs
sounding artificial and “over-produced.” Great singing often doesn’t corre-
spond to the plain-vanilla tuning of a modern piano. Classical singers
sometimes make sharped notes slightly higher and flatted notes slightly
lower, while rock, jazz, and blues traditions have long involved nuanced
bends around pitch. Misused or overused, pitch correction can erase some
of the human elements that make vocals enjoyable. It’s important to
remember that, like all effects—EQ, compression, reverb, and delays
included—pitch correction can’t make a mediocre singer sound great. (In
fact, if you do want to radically change the way a vocal sounds, your best
bet is a vocoder.) In smaller doses, though, pitch correction can save
recording time and rescue a good but imperfect recording.
Noise Reduction/Restoration
There are a variety of solutions to removing unwanted sound from a record-
ing. You can manually edit out pops and clicks with a sample-accurate
waveform editing tool, though that process can be time-consuming. You
can reduce noise and hiss with filters, but that can remove too much of the
sound you want to keep. You can use noise gates to remove broadband
noise, but that does nothing for noise that overlaps with your program
General-purpose restoration plug-ins and noise reduction processors are
designed to address these problems in real time, via a combination of
specialized techniques and some of the previously-mentioned, generic
processors, adapted to the purpose. These tools can help with:
Broadband noise: Specialized noise reduction tools remove sounds
like wind, fluorescent lighting hum, hiss, and other noisy sounds. This
includes FFT-based reduction, which attempts to identify noise by its
spectral content. Some processors sample noise from a location on the
recording that contains only that ambient noise; select a portion of the
waveform containing only noise and hit a command like ‘sample’ or
‘learn,’ and the noise reduction plug-in will attempt to remove that
content from the rest of the file.
What noise reduction/
restoration is:
A spe-
cialized plug-in for elimi-
nating unwanted sounds
from a recording, partic-
ularly broadband noise
like tape hiss or air con-
ditioner noise. (Many
general-purpose restora-
tion plug-ins combine
various functions beyond
simple noise reduction.)
How to use it:
plug-in settings to strike
a balance between
removing unwanted
noise and maintaining
the program material
you want heard. With
broadband noise reduc-
tion, this often involves
sampling noise in a spot
on the recording where
only the noise can be
heard.This “noise profile”
can then be applied to
the rest of the track.
When to use it:
restoration tools usually
can’t rescue recordings
that are so far gone that
you hear mostly noise,
they are useful for fixing
more minor problems
like removing hiss, venti-
lation noise, vinyl pops,
and related issues

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