Positions 1 and 2 are about three feet directly in front of the loudspeaker system, positioned halfway between the middle and high frequency components. These measurements can be used as a control of the basic system functions.
Position 3 is about seven feet in front of the stage centre. Measurements taken here should show an identical response above 250 Hz as obtained from positions 1 and 2. Due to the summing of both loudspeaker systems, the level below 250 Hz should be 3 dB higher.
Position 4 is some way back from position 3, directly in front of the FOH mixing position. (FOH means front of house). The measurements here should be the same as at position 3, with a lower level.
Positions 5 and 6 are on the axes of the two loudspeaker systems, three feet away from the rear wall. These measurements are used to detect any problems caused by standing waves or reflections.
Make sure to save the resulting frequency response curves for comparison purposes. Any major differences between the various measurements should be interpreted as warnings of phase problems within the system or acoustical problems in the room. If you are not able to deal with the source of these problems (by moving speakers, or changing the venue), then you can only attempt to find a workable compromise with the equalizer. For this purpose, the various stored measurements will be of great assistance.
After reaching the desired frequency settings on the equalizer, walk around the room and pay particular attention to any change in the sound as you move around. Don’t forget to periodically listen to your reference music and spoken material to help “refresh” your ears and particularly to get a more objective feeling for the characteristics and sound of your system and the room.
You must be prepared to invest plenty of time and patience to obtain an effective equalizer setting! Beware of using extreme settings to achieve the sound you are looking for. They are inevitably a warning that something is wrong with your system.
An equalizer cannot compensate for a bad sound system, however it is a flexible and very useful tool for fine tuning sound. With practice you will see that subtle changes brought about with the equalizer can greatly enhance the ability of your system to deliver a clear, well defined sound, measurably improving its overall quality.
3.2 Using the
In using the
The feedback destroyer enables you, during sound check, to locate and control any frequencies causing feedback problems. (In this case, having detected a problem frequency, you match the filter to the frequency by switching to either SGL (Single Shot) or OFF (static) in the FB D menu).
In the case of microphones which are constantly moving (typically hand held vocal microphones) the feedback conditions are continuously changing. Use the feedback destroyer filter in searching mode (“S”) to compensate for this.
The feedback destroyer is only suitable for use with signals with a large, changing dynamic (speech, singing, percussion). Long, static signals such as synthesizer or flute, whose sound characteristics have similarities to sine waves, cannot be distinguished from feedback, resulting in their signal being constantly dampened.
If, in „SEARCH“ mode, all the available filters are being used, in the case of a new frequency being found, the “oldest” filter in use will be released from its set frequency and made available for the new one.
The feedback destroyer cannot work miracles! It is capable of raising the feedback threshold by several dB. Seeing the feedback destroyer switching on should be interpreted as a warning signal. Lower the overall volume on stage.
+The feedback destroyer remains active in all (graphic) EQ menus. In the setup menus as well as the level meter menu the parameters of all filters are fixed. The feedback destroyer pauses activity in these menus.
In principle the stage volume really should be kept as low as possible, because:
1.It is better for everybody's hearing,
2.it results in fewer feedback problems and
3.it is easier to get a good FOH sound.
The monitor level tends to rise during the course of a concert. Therefore you should use any pause in the concert to reduce all monitor levels by about 3 dB. This reduction will, if at all, be barely noticeable to the
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