Using The Rta To Ring Out Monitors - PRESONUS studiolive III series Owner's Manual

10 Graphic EQ
10.3

Using the RTA to Ring Out Monitors

Using the RTA to Ring Out Monitors
10.3
Every Graphic EQ is equipped with a Real-time analyzer, or RTA, in which
x = frequency and y = amplitude. As previously mentioned, an RTA provides a close
visual representation of what you are hearing. It provides a view of the long-term
spectrum of the signal—for example, the one- third-octave spectrum long-term
average of a musical performance.
Feedback is short term for a feedback loop, where a portion of the signal from the
speaker returns to the microphone, resulting in a constant tone at the offending
frequency. "Ringing out" is a process of attenuating the frequencies that are feeding
back to maximize gain before feedback in your floor monitors.
1. With the mic input gain at an appropriate level, bring the aux- send level up on
the mic channel you wish to ring.
Power User Tip: If you are using one console for stage monitors and another console for
front-of-house, set the mic input gain on the front-of-house console. Do not "gain up" the
mic signal on the monitor mixer for the sake of getting more volume out of a stage
monitor, as you can do that in other places (Mix level for individual channels, Aux Out
level for global control, etc.). Gain staging is very important in order to have a feedback-
free show.
2. Select the graphic EQ for the Aux Mix output of the stage monitor you are
ringing out.
3. Open the Graphic EQ by pushing the GEQ button.
4. Slowly bring the aux output level up until you hear (and see) feedback.
Note: Ringing out stage monitors will produce feedback. If you are not careful, you can
produce a lot of feedback. Do not make sudden gain boosts; go slowly and carefully to
avoid causing any damage to speakers and ears.
5. Feedback will show up as a line peak on the RTA.
6. Lower the GEQ gain control for the offending frequency in 3 dB increments to
attenuate it out of your stage monitor.
Power User Tip: Bring back the level on the GEQ slider to the point just before feedback so
you don't take out too much frequency content and sacrifice overall timbre. Because the
speaker is pointed at the mic, stage-monitor feedback typically occurs in the higher
frequencies, which also is where intelligibility comes from. Maximizing your intelligibility
and gain structure results in clearer-sounding monitors.
You can apply this process to the main system, as well. This is especially useful with
applications requiring lavaliere or podium mics. These types of microphones are
typically omnidirectional condensers and are very prone to feedback.
In a main system, feedback is typically in the mid to low range. The frequencies
that are regenerating and creating a feedback loop are those frequencies that are
wrapping around the main system due to the loss of directional control of lower
frequencies.
When you are ringing out a system, and more than two or three feedback loops are
happening simultaneously, you have reached the level where stability can no longer
be achieved. Try bringing down the overall output level or find a physical solution,
such as moving the speaker or microphone.
StudioLive™ Series III
Owner's Manual
86