Viking MCX-106 - Manual (Page 10)

Before connecting other equipment to the Powered mixer,
check the impedance and level of both. If the impedances
and levels do not match, mixing will be very d i f f i c u l t and
the S/N ratio will also be adversely affected.
Each input channel of the MCX-106 is provided with a
TRIM control. Thorough understanding of the f u n c t i o n of
a TRIM control will make mixing easier.
The function of the TRIM control is to control the negative
feedback volume of the head-amp so that the gain of the
head-amp can also be changed. Because of this, enough
dynamic range, even for high level signals is ensured.
Also, the S/N ratio will be better by decreasing the gain of
the head-amp.
For example, a keyboard, a musical instrument and a
dynamic microphone with output levels of —l0dBm,
-20dBm and -40dBm respectively are connected to the
MCX-106.
If the trim control is set as shown in the l e f t figure, the
i n p u t level controls can be set to t h e same position.
The i n p u t level controls are used in general between 6 and
8.
The peak indicator LED i l l u m i n a t e s if the head amplifier
or equalizer is clipping. The gain of the head-amplifier
must be decreased by t u r n i n g the t r i m c o n t r o l counter-
clockwise.
Key Board in Musical Instrument in Dynamic
—l0dBm level —20dBm level Microphone in
-40dBm level
The f o l l o w i n g p r o c e d u r e s are r e c o m m e n d e d f o r an
accurate and h i g h - q u a l i t y r e c o r d i n g .
1. Place the level meter selection switch in the "Tape"
position.
2. Engage the noise r e d u c t i o n c i r c u i t r y by p r e s s i n g t h e
dbx switch.
NOTE:
Using the i n t e r n a l dbx c i r c u i t r y will p r o v i d e h i g h e r
q u a l i t y recordings w i t h excellent "signal-to-noise"
c h a r a c t e r i s t i c s . You will n o t i c e a d r a s t i c r e d u c t i o n
in audible "tape hiss" and a s i g n i f i c a n t i n c r e a s e in
d y n a m i c range. H o w e v e r , the dbx noise r e d u c t i o n is
an "encode/decode" process, m e a n i n g t h a t any tape
t h a t is recorded w i t h dbx m u s t also be p l a y e d back
w i t h d b x , to o b t a i n s a t i s f a c t o r y r e s u l t s . If the
r e c o r d i n g m u s t be p l a y e d on o t h e r e q u i p m e n t
w i t h o u t dbx c i r c u i t r y , we r e c o m m e n d t h a t t h e dbx
f e a t u r e not be u s e d .
3. Press t h e r e c o r d b u t t o n t o p l a c e t h e deck in "record
pause" mode.
4. A d j u s t the L and R m a s t e r r e c o r d i n g level sliders to
a l e v e l j u s t b e l o w t h e "red" in t h e b a r g r a p h m e t e r s .
5. Press PLAY b u t t o n t o b e g i n r e c o r d i n g .
Fault
Excessive current due to
overloads.
Short circuits
(less than 0.4-ohm)
Temperature rise of heat
sink
(more than 105°C)
DC drift
Protection
Current limiter activates at
less than 1 ohm.
Current limiter activates,
input signal is lowered,
unit shuts down.
Input signal is lowered.
Unit shuts down.
Input signal is lowered.
Unit shuts down.
Indication
Compressor
LED illuminates.
Amp protection
LED illuminates.
Amp protection
LED illuminates.
Amp protection
LED illuminates.
Action
Remove excessive lords.
Minimum speaker loads 2-
ohm.
Check speaker
lines/systems for shorts.
Check for adequate
ventilation.
Refer to qualified service
personnel.
Restoration
A u t o m a t i c restoration
a f t e r normal loads are
obtained.
Turn off power switch.
Turn on into operational
loads.
A u t o m a t i c restoration
a f t e r temperature
lowers (to 75° - 95°C)
A u t o m a t i c restoration
after normal bias is
regained.
Fault Protection Table
— 9 —
How to get a good mix
Recording Level Setting