Behringer Eurolive VP1220F Manuale Proprietario

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EUROLIVE VP2520/VP1800S/VP1520/VP1220F/VP1220 User Manual
(2) 
The VP series includes two parallel ¼" TS loudspeaker
 (2) 
inputs. You can 
connect one of the connectors to the output on your power amp and tap 
into the signal from the amp on the second connector, in order, for example, 
to feed this signal into an additional loudspeaker.
strain relief clamp
sleeve
tip
sleeve
(ground/shield)
Unbalanced ¼" TS connector
tip
(signal)
Fig. 2.3: ¼" TS loudspeaker connector
◊ 
When several loudspeakers are wired in parallel the overall impedance 
Z
T
 to be handled by the power amp can be calculated, as shown below, 
from the individual impedance values of the connected speakers:
For the VP series, here are typical connection scenarios:
Two 8 Ohm speakers in parallel = 4 Ohms
Four 8 Ohm speakers in parallel = 2 Ohms
Two 4 Ohm speakers in parallel = 2 Ohms
Four 4 Ohm speakers in parallel = 1 Ohm
◊ 
Your amplifier may be damaged if the actual impedance drops below 
its input impedance. Please make sure that the calculated total 
impedance Z
T
 is not smaller than the minimum impedance specified 
for your amplifier.
3.  Optimal Operation
We have developed the VP series for use in a wide range of possible applications. 
Of course, the sound of your loudspeakers depends on the acoustic characteristics 
of the room/space in which they are being used. The following chapters of 
this manual will give you information about getting the most out of your 
EUROLIVE loudspeakers.
3.1  Loudspeaker placement
Here are some tips to get optimal sound and performance 
from your loudspeaker(s):
Elevate the loudspeaker at or above head level. High frequencies are 
the segment of the audio spectrum responsible for clarity and speech 
intelligibility. They can get muffled by the front row of the audience, so we 
recommend positioning your loudspeakers so the high-frequency drivers are 
slightly above the height of the audience. The more you can get everyone in 
direct earshot, the better. Imagine the loudspeaker is a giant flashlight,  
and you want to illuminate everyone in the room
Avoid placing full-range loudspeakers in a corner or right next to a wall. 
This enhances the low frequencies and can cause the sound to get muddy. 
Subwoofers may be placed almost anywhere since low frequencies are not 
highly directional
Make sure that the loudspeakers are not in a place where they could 
be knocked over by dancing audience members, overly eccentric stage 
performers, sudden earthquakes, etc.
Some rooms, such as gymnasiums and auditoriums, create a large amount 
of natural reverb, making it difficult to maintain intelligible sound. 
Laying carpet or rugs on the ground and curtains across windows or brick 
walls will help dampen the reflections and improve the overall sound
3.2  How to prevent feedback
Always place the “front of house” speakers ahead of the microphones 
(from the audience’s perspective), and never behind. Use professional floor 
monitors or an in-ear monitoring system to allow the stage performers to hear.
3.3  How to avoid feedback when working with 
record players (DJ Applications)
In applications with record players, bass feedback can occur. Bass feedback 
occurs when low frequencies get back to the pickup and are reproduced on the 
loudspeakers. The most common causes for this are: speakers located too closely 
to the record player, a room with a wooden floor, or presence of a podium or a 
platform. In such cases, it is best to move the loudspeakers away from the record 
player and remove them from the stage, so that they are located on firm ground. 
Another option is to use raised stands, which prevent the loudspeakers from 
having a direct contact with the ground.
3.4  Loudspeaker protection by  
using a low-cut filter
Try to prevent damage to your loudspeakers caused by extreme oscillation 
of the low-frequency driver due to subsonic noise and extremely deep 
frequencies. Use an equalizer to cut off those frequencies that fall below 
your loudspeakers’ frequency range, or use a low-cut/high-pass filter. 
Most equalizers and sound-improvement systems offer a low-cut function, 
like the BEHRINGER ULTRAGRAPH DIGITAL DEQ1024, for example. Using a low-cut 
filter in your signal path is particularly recommended if you use record players 
or CD players as your signal source. CD players often produce extremely deep 
frequencies, which can lead to extreme excursions of the low-frequency driver.
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