Hartke LX5500, Руководство пользователя

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LX Series Bass Amplifier 9
About Compression
The dynamic range of a sound is the difference between its loudest and softest levels. For example,
as you play your bass, you’ll probably find that some notes (such as notes played on
the upper frets of the lowest string) are considerably louder than others. The function
of the compression circuitry in the LX amplifier is to reduce overall dynamic range
by automatically reducing the level of the loudest sounds you play so that they are
closer in level to softer ones. The end result is a smooth, even sound.
The front-panel COMPRESSOR control determines the amount of compression (peak signal
reduction) by adjusting the threshold. Threshold is the limit above which compression is applied.
As you turn the COMPRESSOR control clockwise, the threshold level is lowered. The compression
ratio is set to around 2:1, which means that any input signal over the threshold level will be halved.
The LX amplifier’s compression circuit follows the incoming signal, and will adjust the compression
ratio down when you play notes with fast attack to avoid “squashing” your sound. This is useful
when playing fast staccato passages as it will cause all the notes to sound at the same level, even if
the signal is above the threshold level.
The LX5500 & LX8500 provide front-panel compression lights that visually indicate when the
audio signal crosses the threshold level and activates the compressor circuit. When lit white no
compression is being applied. When the indicator lights red compression is being applied to the
incoming signal.
Compression has three main uses. First, as described above, it “evens” out the notes played by
your bass so that they all are at virtually equal levels. Second, it adds “punch” to a sound. Since
all levels are nearly the same, you can play with greater force without worrying about the loudest
notes distorting. Finally, it serves to protect your loudspeakers from damage as a result of brief
(transient) high output levels, which might otherwise be caused by slapping, finger-popping or other
playing techniques & styles.
Whether or not you need to use compression with your LX amplifier will be a matter of personal
taste and playing style. Experiment and see if you like the effect. If you usually play at low volume
levels, you’ll find that even with the COMPRESSOR knob turned up, the compression circuitry may
have no audible effect. In general, if you don’t need compression, leave it off.