Altair EQ-215, Руководство пользователя

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OFF, according to the faders state setup switch , placed at the graphic equaliser rear
panel.
LEDs ON:
In this switch position, the LEDs associated with the fader, remain lighting, give rise to
a greater visibility in darkness places.
SCAN (ONLY EQ-230):
With the switch placed in this position, the graphic equaliser LED associated with the
fader light when take place a feedback (feedback finder system). When a feedback take
place, the corresponding LED associated with the near band in that the feedback is, light,
if the feedback is between two bands, the corresponding LEDs light alternating, indicat-
ing that the feedback is in a intermediate position. This feedback finder system, allow a
greater speed in the feedback elimination by the sound engineer, as well as a greater
security that the feedback is in the indicated frequency.
The feedback finder system can make a mistake with sine signals, like the generated
by wind instruments, by this the system can fail in same occasions, indicating an nonex-
istent feedback, on the other hand, the sound engineer must distinguish between a real
feedback an a sustain flute note, by this, the inconvenient don't cause greater problems.
LEDs OFF:
In this switch position, the LEDs associated with the fader, remains off .
6. SOUND SYSTEM EQUALISA TION
Before starting the description of the equalisation procedure, we will try to justify this
equalisation. In the real world, very few things are perfect, and the same happens to the
sound systems, and even if we had a perfect speaker, the room in which we are going to
work is nor perfect either, because the floor, the walls and the ceiling are not absorbent at
all, and they produce resonances, stationary waves and its own sound, making an imperfect
system with our perfect speaker. The open-air system have the same problem, because the
floor is in the same place, and in many cases the walls as well, and the most important of
all: the speakers are not perfect.
You must as well bear in mind that no equalisation suppress the problems caused by
reflections, stationary waves and excessive resonances.
After this explanation, before starting to equalize, if the sound system is multiamplified,
adjust the crossover controls in such a way that they produce the best way of overall re-
sponse (if using an spectrum analyzer) or if you are going to equalise by ear, adjust combin-
ing the two more important factors, that is, the power and the intelligibility, that is to say, the
system must give the maximum of power and has to be intelligible.
We advise the use of an spectrum analyzer, because our ears are not reliable: our
auditive memory at long term is poor, our audition process is very adaptable, because it
adjust itself to compensate different conditions, the sound pressure level and the changes in
tone. When a change takes place, our auditive sense can detect it clearly (short term auditive
memory), but ours ears are not good remembering something at long term, specially when
there are sounds without relation between the remembering periods.
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ALTAiR
EQ-215/230 GRAPHIC ECUALISERS