5 Microphone technique
DHTTetrad handheld transmitter
DMSTetrad
A handheld vocal microphone provides many ways of shaping the sound of your voice as it is
heard over the sound system.
The following sections contain useful hints on how to use your DHTTetrad handheld transmitter
for best results.
Working distance and proximity effect
Basically, your voice will sound bigger and mellower, the closer you hold the microphone to your
lips. Moving away from the microphone will produce a more reverberant, more distant sound as
the microphone will pick more of the room's reverberation.
You can use this effect to make your voice sound aggressive, neutral, sensual, etc. simply by
altering your distance from the microphone.
The proximity effect is a powerful increase in low frequency response that occurs when a sound
source is close to a microphone (less than 2 inches / 5 cm). It will give your voice a voluminous
and punchy quality.
Angle of incidence
Sing to one side of the microphone or above and across the top of the microphone. This provides
a well-balanced, natural sound.
If you sing directly into the microphone, it will not only pick up excessive breath noise but also
overemphasise "s", "sh", "tch", "p", and "t" sounds.
Feedback
Feedback occurs when part of the sound emitted by the loudspeakers is picked up by the
microphone, amplified and retransmitted to the loudspeakers. As of a certain volume (the
feedback threshold) this signal virtually loops, the system emits beeps and other shrill noises and
can only be controlled again by turning down the volume control.
To avoid this, the microphone of the handheld transmitter DHTTetrad features a capsule with
supercardioid polar pattern.
This means it reacts most sensitively to sound coming from the front (voice), while it hardly reacts
to sound coming from the side or the back (e.g. from monitor loudspeakers).
To ensure a minimum of feedback, place PA loudspeakers in front of the microphones (at the
front edge of the stage).
If you use monitor loudspeakers, never point the microphone directly towards the monitors or the
PA loudspeakers.
Feedback can also be triggered by resonance effects (due to room acoustics) especially in the
lower frequency range (proximity effect). In this case, simply increase the microphone distance
to stop the feedback noise.
Backing vocals
1) Never let more than two people share a microphone.
2) Backing vocalists should not sing at more than 35° to the microphone axis.
The microphone is very insensitive to sounds arriving from the side. If the two vocalists were
to try and sing into the microphone at an angle of more than 35° to the microphone axis, you
would have to turn up the level of the microphone channel high enough to cause a feedback
problem.
Microphone technique
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