Table of Contents
Advertisement
SECTION THREE
.
Detailed Instructions
The photos and callouts in Section | may serve as a
useful reference while you read the following instructions.
It also may be helpful to study the specifications,
especially when considering how to use your mixer with
an accessory device,
INPUT CHANNELS
Each channel has two input jacks. The standard phone ,
jacks are intended for use with high impedance (Hi-Z) or
low impedance (Low-Z) sources, while the 3-pin XLR
connectors are strictly for low impedance inputs.
Input jacks
NOTE: Most Low-Z microphones (nominal 150 ohms)
are designed to work into loads of approximately
900-1500 ohms. These load values are provided by the
Low-Z XLR connectors, but not by the phone jacks.
Connecting your Low-Z mics to the wrong input
(High-Z) can alter the microphone's frequency response.
Conversely, connecting a High-Z mic to a Low-Z input
can overload the mic, lower the level and adversely
affect the mic's frequency and transient response.
Input Level Switch
On the Models ЕМ-10011 and EM-15011B, this is a
3-position slide switch, labeled MIC/INST/LINE.
LINE
INST
MIC
un
ЕМ-10011 & EM-15011B input level switch
In MIC position, the channel input sensitivity
(—50 dB) is optimum for a high-impedance microphone.
The cables used with high-impedance (High-Z) micro-
phones should be shielded, and no longer than 25 feet.
If your application requires longer cables, we suggest
the use of the optional Transformer Balancing
Modules (not available for ЕМ-10011) and low impedance
microphones. Medium-impedance microphones, including
many electret condenser microphones, can be connected
directly to the Mixer without an auxiliary transformer,
provided that the mic output level is sufficiently high.
In INST position, the channel's input sensitivity
(—35 dB) is optimum for non-amplified instruments
such as electric guitars or other instruments equipped
with electro-magnetic pickups.
in LINE position, the channel' $ sensitivity (—20 dB)
is optimum for "direct" or "preamp" outputs from
amplified instruments like a synthesizer or electronic
piano.
Input Level Switch -
On the Models EM-200B and EM-300B, this is a
5-position rotary knob labeled for nominal input ,
sensitivities of —50, —40, —30, —20, and +4 dB. The
10
EM-200B & EM-300B input level switch
—50 dB setting is commonly used with low output
dynamic microphones, —40 dB with medium output
condenser microphones, —20 dB with electric instru-
ments (preamplified) and low level (creative audio or
hi-fi) line sources, and *4 dB with high level line sources
(such as most professional equipment line outputs).
NOTE: The +4 position may not be used when the
optional Transformer Balancing Module is installed.
Set the Input Level switch to correspond to the type
of device that is plugged into the corresponding
Channel Input jack. Here is one suggested procedure:
1. Connect all input sources to their respective
channels. Plug in and wear your headphones to hear the
program mix. DO NOT CONNECT any speakers yet.
|
2. Set all channel faders at zero (minimum). Set each
channel Pan control all the way to the Left, and raise
the Left Master Program fader to #9.
|
3. Start with the Input Level switch in the least
sensitive position ("Line" ог +4 dB). Bring the channel
fader up to #7. 1f necessary, adjust the Input Level
switch for greater sensitivity, one "click" at a time,
until the input is clearly audible. The Left VU meter
should peak around "0 dB". If the meter consistently
shoots past "0 dB", or if the signal sounds distorted
in your headphones, the Input Level switch is set for
too much sensitivity (too low a dB #}; decrease the
input sensitivity (higher dB # on the Input Level switch)
until the levels are correct.
4. Repeat the procedure for each input channel, until
all channels are set for proper input sensitivity. Turn the
Mixer Power OFF, and connect your speakers and
|
outputs. Set both Master Program faders to about #7
|
and turn the mixer power ON again. You are now ready
to adjust each channel fader, EO, and stereo assignment
|
(Рап).
|
. CAUTION: DO NOT CONNECT THE SPEAKER OUT-
PUT OF ANY AMPLIFIER TO THEMIXER
UNLESS
A SUITABLE HIGH-LEVEL ATTENUATION
PAD OR
"DIRECT BOX" FIRST LOWERS THE LEVEL.
|
NOTE: Always turn Master faders (Program and Monitor)
all the way DOWN before turning the AC Power ON.
The channel fader adjusts the level applied to the
stereo program mix bus from whatever source is
connected to the channel's input jack. This allows you
to set precisely the level for various mics and/or
instruments, thereby achieving just the desired mix
(blend) of these sources.
The Low-EQ control adjusts the channel's frequency
response through the low-frequency range. The control
Advertisement
Table of Contents
