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INTELLIGATE XR2000
Similarly, with a fine adjustment of controls mentioned, the dynamic range of an instrument can be artificially
expanded. Expansion can achieve good results, expecially with sampled sounds, because samplers only have
a heavily restricted dynamic range. When processing drum sounds (e.g. a snare), downward expansion can
result in insteresting effects. If for instance the threshold is set to an intermediate level, then only the lower part
of the dynamics will be processed. The decay of the signal follows naturally to the adjusted threshold and is
then faded out more intensively.
3.2
Correct microphone placement
The main task of an expander is to “inaudibly” seperate undesirerable background noise from wanted signals.
This process requires that the signal level appears slightly above the noise floor in order for the threshold level
to be defined accurately.
The optimum use of the expander depends principally on microphone technique.
Be particularly careful, when high frequency instruments are located to the side or rear of a cardioid microphone.
Most cardioids exhibit a sharply rising off-axis response characteristic at higher frequencies. If there is only a
2 or 3 dB difference between the on-axis and off-axis response in the 5 to 10 kHz region, cymbals may leak
excessively into the tom mics and you may have hi-hat spilling all over the snare mic.
Please make full use of the directional characteristic of the mics, to acoustically exclude all other instruments
as much as possible. Make sure that you do everything possible to achieve source separation with good
microphone technique. Otherwise the expander is not able to undertake clear acoustic separation.
Nevertheless there are situations, where even ideally suited microphone techniques cannot provide you with
the desired effect. The BEHRINGER INTELLIGATE gives you frequency selective expansion as a further aid to
acoustic separation:
3.3
Frequency selective expansion
Sometimes, it is necessary to prevent the expander from responding to low frequencies (rumbles etc.), especially
if a singer is moving the microphone around on a mic-stand. Besides this, there are circumstances, when the
programme material is corrupted not only by unwanted random noise, but also by the sound of other instruments.
For example, in a multi-miked drum kit situation, some hi-hat will inevitably leak into the snare mic, some
snare drum into the kick drum mic and so on. Equally when recording on location, you may experience
problems due to wind or traffic noise or close-by conversation. If the unwanted noise is different in pitch to the
wanted sound, it is often possible, by using the key filter section, to prevent the expander from false triggering.
Proceed as follows:
1. Depress the FILTER and the KEY LISTEN switch.
2. Try with the help of the key filters to extensively filter out undersireable signals and at the same time, try to
precisely adjust to the wanted signals.
3. Release the KEY LISTEN switch.
4. Readjust the THRESHOLD control to the new level situation, so that the INTELLIGATE only triggers on the
wanted signals.
3.4
Main applications
3.4.1 Controlling leakage in the studio
Expander/gates are most commonly used to suppress undesirable leakage of sound from one track to another
during recording or playback. They are usually used when recording drum kits, where the mics are very close
to each other.
High volume levels on individual instruments often cause considerable leakage into all the adjacent mics and
results in conflicting frequency and phase coherence problems, as well as unspecified sounds (“comb” filter
effects). It is vitally important, that every instrument is recorded into a separate mic and that each mix is
individually gated.
Insert the BEHRINGER INTELLIGATE into a snare drum channel for example and adjust it so that triggering
only occurs when the snare drum is played. Each mic should be set to its maximum operating level, monitored
(see KEY LISTEN switch) and the THRESHOLD level set so that each snare hit sounds acoustically clean and
separate.
3. APPLICATIONS
