Martin Audio – MA900 Amplifier
E
NGLISH
4
4
INTRODUCTION
Thank you for purchasing a Martin Audio power amplifier. This manual contains important information on operating
your amplifier correctly and safely. Please take some time and read this manual and familiarize yourself with the
advanced features of this amplifier.
4.1
Unpacking
Each Martin Audio MA series amplifier is built to the highest standard and thoroughly inspected before it leaves the
factory. After unpacking the unit, examine it carefully for any signs of transit damage and inform your dealer if such
damage is found. It is suggested that you retain the original packaging so that the unit can be repackaged at a
future date if necessary.
Please note that Martin Audio and its distributors cannot accept responsibility for damage to any returned product
through the use of non - approved packaging.
4.2
Front panel
PROTECT
CLIP
-4 0dB
ON
MA90 0
0
1
8
3
2
4
5
7
6
1
1
1 . In pu t leve l atte n ua to rs
T he se co ntro ls are u se d to se t the sign al le ve l e nterin g the am plifier. T he y are calibrated in d B 's to a ssist the se tu p o f
a ctive lou dsp ea ke r syste ms. (Se e p ag e
1
2
).
2 . Prote ct in dica to r
This indicator illuminates if the amplifier attempts to function above its maximum operating temperature (90°
°
C).
The indicator first comes on as a warning, to either turn down the input level or check the cooling arrangements,
after which point the amplifier will mute the input signal. When the cooling fans have returned the output heat sinks
to the normal operating temperature the input signal is un-muted.
T he p ro tect L ED a lso illu mina te s w he n con sta nt sign als a bo ve 12 kHz at fu ll p ow e r are d etected a t the o u tp ut
termina ls or if the sh ort circu it pro te ctio n is a ctivate d. If this o ccurs the in pu t sig na l is mu ted , an d the process rep e ats
u ntil th e VH F sig na l is n o lo ng e r pre se nt o r the sh ort circu it is re mo ve d . (S ee pa ge
1 3
).
3 . Clip /limit ind ica to r
T his in d icato r sign a ls w h en the am plifier o u tp ut is clip ping or lim iting . It ha s two differe nt in dica tio n sta te s:
W he n th e clip lim ite r is en ga ge d , it ha s a sho rt time co nsta n t an d it illum in ate s briefly. (Se e p ag e
1 3
).
4. Signal present indicator.
T his LE D Illu mina te s a t – 40 dB b e lo w full ou tpu t sig na l.
5 . On in dica tor
The two bottom green ”ON” LED's indicate that the output circuits are receiving the correct rail voltage.
6 . P ow er sw itch
T urns th e ma ins p ow e r “O N” o r “OF F”.
(See page
8
and
1
1
)
All material © 2007. Martin Audio Ltd. Subject to change without notice.
