(System Connection - continued from first page...)
the LINE IN is not used, it automatically grounds inter-
nally. This allows the MIC/LINE switch now to act like a
mic mute
switch since selecting LINE sees a grounded
input.
The input channel INSERT LOOP allows any external
processor to be tied in series with the input source before
the MASTER and AUX Level controls. It is wired per the
tip = send/ring = return convention.
A pair of RCA input jacks allow hook-up of a Tape
Player, Tuner or CD Player. Use the MONO switch to
combine the stereo inputs as required.
OUTPUTS. High-current cross-coupled amplifers drive
each of the four main outputs. The MASTER 1 OUTS
leave through terminal strips while the MASTER 2 OUTS
exit through 3-pin connectors wired per above. Use stan-
dard balanced wiring procedures of NOT connecting
ground between units, and grounding the shield only at
ONE end. If for some unforgiveable reason you run unbal-
anced, then you MUST short pin 3, or the “–” terminal to
pin
1
or ground.
Cross-coupled output stages demand
GROUNDING of the unused output when operated unbal-
anced.
The AUX OUT/IN jacks serve two functions: 1) As
Auxiliary Outputs use normal mono (l-wire) unbalanced
1/4" cable and connectors; 2) For effect box use, use stereo
(2-wire) 1/4" TRS interconnecting cable and connectors
wired per the standard insert loop convention of
tip= send/ring= return. Since the AUX OUTS are unbal-
anced, they CANNOT be used to drive long (greater than
100 feet or 30.5 meters) lines. The unbalanced TAPE OUT
RCA jacks should be treated similarly, i.e., restrict their
OPERATING INSTRUCTIONS
SETTING MIC GAIN CONTROL.
Use the exact micro-
phone for each input and approximate expected normal pro-
gram levels and content. Observe the OL (Overload)
indicator (above and to the right) as you increase the MIC
GAIN control. The proper setting is when the OL light oc-
assionally flickers with program material, but does not
come on steady for long periods of time. The best signal-to-
noise performance results from taking as much gain as pos-
sible at this stage. The OL indicator located at the top front
of each input channel is a duplicate of the one in the rear.
If an input sounds distorted, check these lights and turn
down the MIC GAIN as necessary.
USING THE MIC/LINE SWITCH.
Choosing between
the MIC and LINE inputs is done with this slide switch.
The LINE input is a bonafide separate input (not a pad in-
serted in the MIC input), which allows both inputs to be ac-
tive and selected at any time. Additionally, the LINE input
is automatically grounded when NOT in use, which lets
this switch then act as a MIC MUTE.
The CM 86 is supplied with a rear mounted LIFT
(ground-lift) switch. The unit is shipped with this switch
in the “grounded” position, tying circuit ground to chas-
sis ground. If after hooking up your system it exhibits
excessive hum or buzzing, there is an incompatibility in
the grounding configuration. Your unholy task is to dis-
cover how this particular system wants to be grounded.
Here are some things to try:
1. Try combinations of lifting grounds on units sup-
plied with ground lift switches or links.
2. If your equipment is in a rack, verify that all chassis
are tied to a good earth ground, either through the line
cord grounding pins or through the rack screws via an-
other grounded chassis.
3. Units with outboard power supplies do NOT ground
their chassis through the line cord. Make sure that these
units are grounded either to another chassis which
is
earth grounded, or directly to the grounding screw on an
AC outlet cover by means of a wire connected to the
CHASSIS GROUNDING SCREW.
CHASSIS GROUNDING
IMPORTANT NOTE
Please refer to Rane Note 110 (supplied with your unit
and available on request at no charge if you lost your
first one) for further information on system grounding.
FLEX BUS.
The Flex Bus allows you to expand the CM
86 using either another CM 86 or any of the Flex bus mod-
ules. The bus carries four signal lines (Master A & B and
Aux A & B) and two spare. The signal lines come into the
CM 86 via the FLEX BUS IN connector, sum with all
local inputs and exit via the FLEX BUS OUT connector.
This mixing is done before the Master Insert Loops. Signal
comes straight in, mixes into the four summing buses and
goes straight out. The two spare lines simply tie the bus
connectors together. See the FLEX USERS GUIDE for ad-
ditional details.
FOUR INDEPENDENT OUTPUT MIXES.
The CM 86
allows you to create up to four independent output mixes:
MASTER A, MASTER B, AUX A and AUX B. For true
independence of the AUX mixes, remember to position the
assign switches to the PRE position, otherwise changing
input LEVEL controls also affects AUX levels.
Observe that MASTER OUT 1 and MASTER OUT 2 are
the
same mix,
but may be set for different levels.
Copyright 1992, Rane Corporation 10802 47th Ave. W., Mukilteo, WA 98275-5098 (425)355-6000
All features & specifications subject to change without notice.
520-230 892