ART Pro Audio XL231 - Dual 31-Band, 1/3 Octave, Graphic EQ - Manual (Page 14)

ART XL 231 Dual 31 Band, 1/3 Octave Extended, Long Throw, Professional Equalizer
14
Tuning a sound system by ear.
To tune a room by ear also makes sense. Test equipment won’t always indicate what
sounds best. Acoustic environments are very complex and many tradeoffs are made.
System performance can vary quite a bit from one listening position to another. Not only
does frequency response vary, reverb decay times verses frequency can vary also.
The human hearing system is quite complex and often is the best piece of test
equipment when it comes to room tuning.
Select Source Material:
Choose a piece of source material. You may want to experiment with trying different
sources such as:
1) a music CD that uses a lot of the audio spectrum. If the system is being set up for a
particular performer, then a recording of that performer may be a good choice.
2) A music CD that the user is very familiar with.
3) A pink noise generator.
Having multiple sources to experiment with is useful for testing the system.
Step-by-step:
With the system up and running, start with the equalizer set to a flat position. To tune
the room, with source material playing, working on one frequency band’s slider at a
time, move the slider very high so the signal in that band dominates the overall signal.
Listen to what you hear in this band. Slowly decrease the slider to the point where you
can barely hear that band. Then lower it just a bit so the energy in that band gets buried
in all the other sound. Repeat this for each frequency band.
After the first tuning, try different source material and perform the tuning again. As more
tuning is done, the improvements will be smaller and smaller. Stop tuning when the
improvements are very small.
The tendency for users new to this is to end up with all bands boosted by some amount.
Try to learn not to do this. Practice by boosting each band from center and returning it to
center. The way that a single band’s energy disappears in the overall sound is what you
want to train yourself to hear. With practice, you will find room tuning to become easier,
and, quicker.
When tuning is complete, while listening to your source material, switch between
ACTIVE and BYPASS to see what you have done. Set the Level so that the overall level
is approximately the same when in BYPASS or ACTIVE, that is normalized.
Ringing out a Room
Setting an EQ by ringing is useful for increasing the available system gain before
feedback. In a live sound system, with stage monitors and separate front of house
system (FOH), only the monitors should be rung out. This is where feedback is most
likely to occur. The FOH should be equalized for the best overall sound. The ringing
method doesn’t necessarily create the best sound.
To ring out the monitors, if available, use a limiter set to infinite slope, a low threshold,
and, set the level low to save everyone’s ears.