Mackie s225 Manuale Utente

Pagina di 12
7
• 
Avoid placing the speakers directly on a hollow 
stage fl oor. A hollow stage can resonate at certain 
frequencies, causing peaks and dips in the fre-
quency response of the room. It’s better to place the 
loudspeakers on a sturdy table or stand designed to 
handle the weight of the S225s.
• 
Position the loudspeakers so the high-frequency 
drivers are 2 to 4 feet above ear level for the audi-
ence (make allowances for a standing/dancing in 
the aisles audience). High frequencies are highly 
directional and tend to be absorbed much easier 
than lower frequencies. By providing direct line-of-
sight from the loudspeakers to the audience, you 
increase the overall brightness and intelligibility of 
the sound system.
• 
Highly reverberant rooms, like many gymnasiums 
and auditoriums, are a nightmare for sound system 
intelligibility. Multiple refl ections off the hard walls, 
ceiling, and fl oor play havoc with the sound. Depend-
ing on the situation, you may be able to take some 
steps to minimize the refl ections, such as putting 
carpeting on the fl oors, closing draperies to cover 
large glass windows, or hanging tapestries or other 
materials on the walls to absorb some of the sound.
 
However, in most cases, these remedies are not 
possible or practical. So what do you do? Making 
the sound system louder generally doesn’t work 
because the refl ections become louder, too. The 
best approach is to provide as much direct sound 
coverage to the audience as possible. The farther 
away you are from the speaker, the more prominent 
will be the refl ected sound.
 
Use more speakers strategically placed so they are 
closer to the back of the audience. If the distance 
between the front and back speakers is more than 
about 100 feet, you should use a delay processor to 
time-align the sound. (Since sound travels about 1 
foot per millisecond, it takes about 1/10 of a second 
to travel 100 feet.)