Frequency response and dynamic range, Self-powered versus passive speakers – Apple Final Cut Pro 6 User Manual

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54

Part I

Audio Mixing

Frequency Response and Dynamic Range

The quality of speakers varies greatly depending on their purpose as well as their price.
For example, speakers in a portable stereo or television are designed to play audio that
has already been mastered by a mixing engineer. Mastered audio such as audio CD,
radio, television, and movie sound has a compressed dynamic range (meaning levels
are fairly consistent and loud).

Speakers and amplifiers that are designed for mastered audio often intentionally
emphasize certain frequencies, as is done with the bass enhancement feature found on
many systems. This may make an audio CD sound better, but it is not recommended for
mixing production sound because you get a false impression of the audio signal. For
example, if your speakers overemphasize frequencies around 2 kHz, you may
compensate during mixing by reducing the intensity of audio around 2 kHz. If you then
play your mix on a different set of speakers with a flat frequency response, the
frequencies around 2 kHz will sound too muffled.

Self-Powered Versus Passive Speakers

Speakers powered by an external amplifier are called passive speakers. When you use
separate amplifiers and passive speakers, a number of factors affect the overall
frequency response and quality of your audio. Instead of using a separate amplifier and
speakers, a simpler option is to use self-powered speakers (speakers with built-in
amplifiers). These have become increasingly popular, especially for studio monitoring
and video editing.

Self-powered speakers deliver more consistent performance because both components
are designed to work together and are housed in a single enclosure. For video editing
systems, self-powered speakers are a good, easy-to-use solution. Self-powered speakers
accept line level inputs, so it’s fairly easy to connect them to your audio interface.

Flat Not

flat

20 Hz

200Hz

– dB

+ dB

– dB

+ dB

1 kHz

5 kHz

20 kHz

20 Hz

200 Hz

1 kHz

5 kHz

20 kHz

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