Dolby Laboratories Spectral Processor 740 Brochure

The Dolby 740 is a two-channel, dynamics-based processor for emphasizing low-level
sonic details in audio programming.
Whether bringing out the subtleties in all aspects of recording,
mastering, postproduction, and live performance, or lending
character to audio broadcasts, the Dolby
provides a high level of flexibility in audio processing. Based on
the versatile filtering characteristics of Dolby SR noise reduction,
this two-channel dynamic processor allows boosting of low-level
signals while leaving high-level signals untouched. Like a
magnifying glass for sonic details, the Spectral Processor allows
you to tailor your sound like never before.
The Dolby 740 processes low-level signals in a side chain, where
as much as 20 dB of boost can be added in low-, mid-, and high-
frequency bands. The side chain's signal is then added to the
original input signal, resulting in an output with the low-level
details boosted, while the high-level signals remain unaffected.
For maximum effectiveness, the threshold below which the
processing occurs, the amount of boost in each band, and
the crossovers between bands are all user-adjustable. A gentle
sliding-band noise reduction circuit providing up to 12 dB of
action is also included, to reduce any source noise that the
low-level equalization process might have emphasized. Other
controls include a stereo link switch and adjustable output level.
The user adjustments described above make it possible to
emphasize ambience, lift harmonics, and bring out otherwise
® 740 Spectral Processor inaccessible details—all without compressing or limiting
transients, increasing overall level, or disturbing the overall
sense of dynamics.
User adjustments for selectively boosting low-level signals allow
broadcasters to tailor the sound for their station, whatever the
format. It conveys all the detail of the original source material
while eliminating the over-processed sound that can fatigue
listeners. When used in conjunction with a conventional
compressor/limiter, the Spectral Processor adds greater
punch, presence, clarity, and loudness to broadcast signals.
740
Spectral Processor