Applications
Using the Expander/Gate to Remove Hiss and Noise
The S•com 4 is an extremely useful tool in reducing the level of unwanted noises. By using the Expander/Gate
you can effectively fade the noise into the noise floor or abruptly turn the unwanted signal completely off.
Let's say you want to reduce the bleed or cross talk that occurs when different instruments are recorded in close
proximity to each other. You have recorded an acoustic guitar simultaneously in the same room as with some
other acoustic instruments. The problem is that you hear a lot of the other instruments playing when the acoustic
guitar is silent. This can cause phasing and comb filtering problems due to microphone placement, so having the
bleeding signal drop into the noise floor is desirable. To do this, set the S•com 4 to Expander mode with the
Release switch to Slow and adjust the Trigger so that the acoustic guitar signal is well above the threshold level.
When the signal from the acoustic guitar track falls below the threshold level, the signal subtly fades into the
noise floor.
Now let's say you're attempting to remove the pick-up noise and hum from a guitar track that was recorded
through a loud amplifier. The hum and noise is most noticeable in-between the rhythm of the performance, so you
want to have the gate close during the silent parts and open during the musical passages. To do this, set the
S•com 4 to Gate mode and adjust the Trigger level so that the gate is open just during the musical guitar parts,
and so that the gate is closed during the silent passages so that the hum and noise is muted.
Gating Drums
Using noise gates on drums is particularly useful in recording and in live sound. When a drum kit is set up with
individual microphones on each drum in a live PA system, there's potential for great sound. However, there are
several gain management problems that can occur. Several microphones like the ones on the tom-toms, will only
be used occasionally and until the time that the tom-tom is actually played, its microphone is merely picking up
unwanted sound from other instruments on stage. This adds a lot of unwanted mush in the mix and also adds to
feedback problems. Use the S•com 4 to gate the signal of the tom-tom by selecting Gate with the Expander/Gate
switch. Now adjust the Trigger control so that the gate opens only when the tom-tom is played, and at the same
time, so that the gate is closed even when the adjacent tom-tom is played. This same technique is useful on
drums that have been recorded on individual tracks. By using the Gate to mute the bleed of the other drums ,you
can effectively reduce the comb filtering produced by phase cancellation due to microphone proximity.
Gating Longer Sounds
When using a noise-gate on sound with a longer decay like piano, it is usually necessary to use a longer release
time. Run the piano signal through the S•com 4 and set the Expander/Gate Release switch to Slow. Adjust the
Trigger level on sustained passages to get the best results. Be sure to listen for the natural decay of the instru-
ment and allow the gate to remain open until just after end of the decay.
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