Behringer Eurolive B415DSP, Руководство пользователя

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EUROLIVE B415DSP
4. APPLICATION EXAMPLES
The TIMED TURNOFF switch activates the automatic turn-
off function:
ON
When the switch is pressed (ON position), the automatic
turn-off function is activated. The loudspeaker is turned
off automatically when it receives no signal for more than
3 minutes. As soon as a signal is received, the loudspeaker
is switched back on.
OFF
When the switch is pressed (OFF position), the loudspeaker
remains switched on and can only be deactivated with the
POWER switch .
A noise-gate allows you to eliminate unwanted noise during
signal pauses. This is done by a circuit that mutes the
output when the signal level drops below a preset
threshold. Use the NOISE GATE control to determine the
threshold below which the noise-gate closes.
The
TH LED lights up as soon as the signal level drops
below the threshold value adjusted with the NOISE GATE
control (the noise-gate closes).
3. SETTING UP THE B415DSP
The sound of your B415DSP largely depends on the room
acoustics. Please observe the following hints to get the most out
of your B415DSP.
3.1 Tweeter
High frequencies are the very part of the audio spectrum that
ensure a clear perception of sound and speech intelligibility.
Although these frequencies can be located most easily, they are
also the first to be blocked acoustically. We therefore recommend
that you set up your speakers on speaker stands (not included),
so that the tweeter radiates its signals slightly above the heads
of the audience. This will ensure both an optimum dispersion of
the high-frequency content and a considerably improved speech
intelligibility.
Fig. 3.1: B415DSP mounted on a stand
3.2 How to avoid feedback
Always place the microphones (viewed from the audience)
behind the B415DSP, never in front of it (Fig. 3.2). When you
wish to adjust the controls on the B415DSP while holding a
microphone, please approach the loudspeaker from the rear to
avoid feedback.
Fig. 3.2: Right and wrong positioning
Since the B415DSP can be placed on the floor at an angle as
shown in the illustration below, you can also use it as a monitor
speaker on stage. In contrast to PA speakers, stage monitors
are used to direct sound towards individual performers on stage.
When microphones are used, it is not easy to position the monitor
speakers, since the microphones are moved around in front of
them, often coming very close. To avoid feedback, it is
recommended that you carefully select and direct the microphones
used. Basically, you should never use microphones with a high
directivity, i.e. with a cardioid or hyper-cardioid polar pattern.
Never hold a microphone so that its main pick-up area points
directly towards the loudspeaker. When you hold it with its less
sensitive side towards the speaker box, you can move closer to
the speaker.
Microphones with a cardioid polar pattern should always be
directed at a 90° angle to the axis of the loudspeaker (Fig. 3.3,
left). Microphones with a hyper-cardioid polar pattern should
always be positioned at an acute angle to the axis (Fig. 3.3,
right).
Fig. 3.3: The B415DSP as a monitor loudspeaker
+
If you encounter persistent feedback problems,
consider using our proven FEEDBACK DESTROYER
PRO FBQ2496 for line-level signals. For signals with
line or microphone level, we recommend our
BEHRINGER SHARK DSP110.
4. APPLICATION EXAMPLES
4.1 Presentations
With just one B415DSP and one or two dynamic microphones,
you can set up a basic audio system with very little effort. Thanks
to the built-in mixer section, you can connect the microphones
directly to the B415DSP. Mount the B415DSP on a speaker stand
for optimum presentation and intelligibility of announcements. If
one B415DSP is not enough, you can, of course, use a second
or even more loudspeakers.
Connecting microphones:
s Turn the LEVEL controls fully to the left.
s Connect your microphones to the MIC/LINE inputs.
s Switch on the B415DSP.
s Turn the LEVEL controls gradually clockwise to set
the volume of your choice. Observe the CLIP LEDs while
adusting the volume. Make sure they never shine constantly
but only light up at peak levels only.
s Use the LINE OUT connector to connect an (optional)
second B415DSP.
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Never place a microphone directly in front of the
loudspeaker owing to danger of feedback! When
operating the B415DSP make sure that you always
stay behind the loudspeaker to avoid feedback.