Drawmer LX20 Dual Expander Compressor - Manual (Page 5)

LX20 OPERATOR’S MANUAL 3
completely by either foot switch or another piece of equipment with triggering
facilities, such as the M401 Midi Management System.
FIRST TIME USERS
First time users are well advised to take the time to familiarise themselves with the
principle of compression and the various controls on the LX20. The best way of
doing this is to select various pieces of pre-recorded material and try various
settings, making notes of the results for the future reference.
Piano is a good instrument for experiment. Due to its highly percussive and touch
sensitive nature, adjustments made to the compressor can have a dramatic effect
on the sound. Increase the COMPRESS control to give about 10dB compression for
each piano note struck. Attack and release controls should be set to mid range (12
o’clock) to start with. Short attack times tend to remove the initial attack peak,
whilst long attack times will tend to exaggerate the effect. When using long attack
times, care should be taken to avoid overloading the recording medium. Using a
short release time will enable the compressor to recover quickly, but it tends to
flatten out the sound to an almost constant level, which can sound artificial. A long
release time allows small, fast variations in level to be heard, but fast repeating
notes will not be individually compressed.
In practice, a compromise is made to suit the application. A piano can be made to
sound rather like an organ by using large amounts of compression (20dB or more)
with a fast attack time and a release time of about 0.5 second. In extreme cases like
this, noise can become a problem. This is also the case when recording vocals. The
expander is a useful device for overcoming this problem.
Set the EXPAND control at !30dB. As the piano note dies away, it triggers the
expander, which shuts the sound off. This avoids the increase in noise as the
compressor pushes the gain up during release. If the expander shuts off the sound
to quickly, increase the release time on the compressor. This also affects the
expander. The expander threshold should also be adjusted so that expansion
commences at the correct level.
SYSTEM OPERATING LEVEL
The LX20 is capable of operation at system levels of +4dBu and !10dBu and is
supplied from the factory set to +4dBu. Your dealer will be able to advise you
regarding system level and make any changes that are necessary.
ANY CHANGES MUST BE CARRIED OUT BY THE DEALER.
DO NOT ATTEMPT TO REMOVE THE COVERS FOR ANY REASON.