Operation Manual
FRONT
&
REAR
CONNECTIONS
(MA200-MA400)
14.
BALANCED
INPUT
CONNECTORS
(1/4"
TRS &
XLR)
These
1/4"
(6.3mm)
TRS
(Tip/Ring/Sleeve)
phone
jacks
and
XLR.
connectors
are
compatible
witfi
balanced inputs
and are
wired
as
Tip/Pin
3 =
(-), Ring/Pin
2 =
(+),
and
Sleeve/Pin
1=
Ground.
Since
the TRS
phone jacks
and XLR
connectors
are
internally
wired
in
parallel,
you can
parallel this
unit
with another
amplifier
by
using either
theLINE1/4"
jack
or the XLR
(depending
on
which
you re
using
to
input your signal)
to
output
the
signal
to
the
input
The
1/4"
TRS
phone jacks
can
also
be
used
for
unbalanced inputs.
For
TRS
phone plugs,
simpiy
connect
the
Ring
to the
Sleeve
(ground).
For
1/4'
TS
phone
plugs,
no
change
is
necessary
impedance
ofless
than
600ohms
is
needed
to
avoid signal loss.
For
short cable runs
an
unbalanced signal input should
be
suitable.
For
stereo (two-channel)
operation,
use
the
inputs
for
both
CH-1
and
CH-2;
for
parallel
or
bridged mono operation,
use
only CH-1
input, (See MODE SELECTOR SWITCH below
for
more
explanation.)
15.
MODE SELECTOR SWITCH
STEREO
&
BRIDGED. Slide
the
switch
to one
of
the
three
positions
for you
application.
.
PARALLEL (MONO) INPUT
-This
mode
allows
both channels
to
operate
in
parallel with
the
same signal
and
without
requiring
a
Y-cord
. In
this mode
the
inputs
for
both channels
are
internally
connected,
so
that
you
only
need
to
feed
a
signal
into
one
of
the
channels.
This
still allows independent level control
of
each channel.
It
also
enables
easy "daisy-chaining" with other
arnps
by
using
the
other
channel
of
input
connectors.
(Note:
Do not
selectthis
"Parallel"
mode when feeding
the
amplifier with
2
separate
signals.)
(Note:
Do not use
both unbalanced
and
balanced cables
in the
same
set-up
as
that
can
unbalance
all the
connections when
daisy-chaining,
resulting
in
hum.)
.STEREO
INPUT -This
is the
most common mode generally
used,
and
allows
independent control
of 2
separate
signals
.BRIDGED
MONO-
This mode combines
the
power
of
both
channels
to
drive
a
single speaker.
In
this mode
the amp
produces
4
times
the
peak power
and 3
times
the
sustained
power
into
a 4 or 8 ohm
speaker
thaneacn
channel
can
deliver
separately
in
stereo
or
parallel mode.
(CAUTION:
Inthis
mode
me
amplifier
can
deliver high power
into
a
speaker. Make sure that
the
speaker,
connectors
and
wiring
can
handle this
output.
Nole
that
for
prolonged
overdriven
outputs into
a
4 ohm
speaker
the
mains fuse
may
blow,
so
care must
be
taken
not to
overload
the
amplifier
in
such
operation.)
Connect
the
input signal
to
CH-1 input
for
bridged mono
16.
VENTILATION
HOLES
The
fan
speed
is
varied auto
Page
6
Reference
Manual