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AM-55 / Sep 2015
A P P E N D I C E S
Common audio processing terms and the parts of the spectrum
they govern are at the bottom of the chart. The top part of the chart
shows the frequency range of common musical instruments heard
on the radio (male and female voice included)
Audio Terms and Wheatstone Processing
So how do you tweak a processor to change its sound “texture”? Let’s start with the
low end…
THUMP/RUMBLE/BOTTOM
These terms describe bass generally found at and below about 80Hz. Good stereo
systems, closed or noise reduction headphones and car audio systems with subwoofers
can usually reproduce the audio way down here. Many times such systems even have their
own complex bass enhancement features. The AM-55 is equipped with a very specialized
bass clipper system. This system is an intelligent clipper that samples the bass frequency
relationship between bands 1 and 2 and is able to make changes to the audio based on
user settings in the five band section as well as the five band limiter.
The bass clipper has a threshold control as well as a style control. This allows you to
select if the bass clipper primarily focuses on Band 1 or when “Bass Style 2” is selected,
both Band 1 and 2. Moving the threshold control clockwise raises the bass clipper
threshold and allows more bass through to the main clipper. Conversely, moving the control
counter-clockwise puts more clipping into the control of the bass clipper.
Other ways of enhancing lower frequencies would be to set the Band 1 to Band 2
crossover at 50Hz or 60Hz in the leveler/compressor section and raising the threshold
