3
I. WARNING NOTICES
SPEAKER DAMAGE
The MXa Series amplifiers are among the most powerful
professional amplifiers available and is capable of pro-
ducing much more power than many loudspeakers can
handle. It is the user’s responsibility to use suitable
speakers with the amplifier and to use them in a sensible
way that will not cause damage.
QSC will not be responsible for blown speakers. Consult
the speaker manufacturer for power-handling recom-
mendations.
Either channel of the MX 3000a amplifier has special clip-
limiting protection circuitry that reduces the signal level at
the onset of heavy clipping. This not only allows the
amplifier to operate at a high average power level without
audible distortion occurring, but it also prevents the
speakers’ being destroyed by excessive clipping. How-
ever, if the amplifier is operating normally and your
speakers fail anyway, it is virtually certain that they could
not handle the high power, despite the lack of clipping.
Even if you reduce the gain using the amplifier’s front
panel attenuator controls, it is still possible to reach full
output power if the input signal level is high enough.
A single high-power crescendo can blow high-frequency
drivers almost instantaneously, while low-frequency driv-
ers can usually withstand very high, continuous power
levels for a few seconds before they fail. Reduce power
immediately if you hear any speaker “bottoming out”—
harsh pops or cracking distortion that indicate that the
speaker voice coil or diaphragm is striking the magnet
assembly.
QSC recommends that you use amplifiers of this power
range for more headroom (cleaner sound) rather than for
increased volume.
SPEAKER OUTPUT SHOCK HAZARD
An MXa amplifier is capable of producing hazardous
output voltages. To avoid electrical shock, do not touch
any exposed speaker wiring while the amplifier is operat-
ing.
RACK MOUNTING PRECAUTIONS
In portable racks, to avoid damage to either the amplifier
mounting ears or the mounting rails, support the amplifier
at all four corners. Contact the QSC Customer Service
Department to order rear support brackets.
CAUTION: To reduce the rish of electric shock, do not remove
the cover. No user-serviceable parts inside. Refer servicing to
qualified service personnel.
WARNING: To prevent fire or electric shock, do not expose this
equipment to rain or moisture.
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
ATTENTION: Pour eviter les risques de choc électrique, ne pas
enlever le courvercle. Aucun entretien de pièces intérieures
par l’usager. Confier l’entretien au personnel qualifié.
AVIS: Pour eviter les risques d’incendie ou d’électrocution,
n’exposez pas cet article à la pluie ou a l’humidité.
AVIS
RISQUE DE CHOC
ÉLECTRIQUE
NE PAS OUVRIR
VORSICHT: Um das Risiko eines elektrischen Schlages zu
vermindern, Abdeckung nicht entfernen! Keine Benutzer
Wartungsteile im Innern. Wartung nur durch qualifiertes
Wartungspersonal.
WARNUNG: Zur vermeidung von Feuer oder elektrischen
Schlägen, das Gerät nicht mit Regen oder Feuchtigkeit in
Berührung bringen!
VORSICHT
GEFAHR EINES
ELEKTRISCHEN SCHLAGES.
NICHT ÖFFNEN!
SAFEGUARDS
Electrical energy can perform many useful functions. This unit has
been engineered and manufactured to assure your personal safety.
Improper use can result in potential electrical shock or fire hazards.
In order not to defeat the safeguards, observe the following instruc-
tions for its installation, use and servicing.
PRECAUTIONS
L’énergie électrique peut remplir de nombreuses fonctions utiles.
Cet appariel a été conçu et réalisé pour assurer une sécurité
personnelle entiére. Une utilisation impropre peut entraîner des
risques d’électrocution ou d’incendie. Dans le but de ne pas rendre
inutiles les mesures de sécurité, bien observer les instructions
suivantes pour l’installation, l’utilisation et l’entretien de l’appareil.