Real World Digital Audio

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

sound.

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.

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PECIALIZED

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ROCESSORS

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:

Adjust

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:

While

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