Reference Manual

CHAPTER 21. LIVE AUDIO EFFECT REFERENCE 320
21.21.1 Dynamics Processing Theory
To understand how to use the Multiband Dynamics device, it helps to understand the four
different methods of manipulating dynamics.
When we use the term compression, we're typically talking about lowering the level of
signals that exceed a threshold. This is how Live's Compressor works, and is more accurately
called downward compression because it pushes loud signals down, thus reducing the
dynamic range. But it is also possible to reduce a signal's dynamic range by raising the
levels of signals that are below a threshold. This much-less-common form of compression
is called upward compression. As you can see from this diagram, employing either type of
compression results in a signal with a smaller dynamic range than the original.
original
dynamic
range
smaller
dynamic
range
downward compression
(common)
original
dynamic
range
smaller
dynamic
range
upward compression
(uncommon)
Downward and Upward
Compression.
The opposite of compression is expansion. A typical expander lowers the levels of signals
that are below a threshold. This is how Live's Gate works, and is more accurately called
downward expansion because it pushes quiet signals down, thus increasing the dynamic
range. It is also possible to increase a signal's dynamic range by raising the levels of signals
that are above a threshold. Like upward compression, this technique is known as upward
expansion and is much less common. This diagram shows that either type of expansion
results in a signal with a larger dynamic range.