Radio Shack 4-Channel Stereo Microphone Mixer User manual

Owner’s Manual
Please read before using this equipment.
4-Channel Stereo Microphone Mixer

2Features
ˆ Features
Your 4-Channel Stereo Microphone Mixer is
a sophisticated control center, perfect for
mixing sound from up to four audio input
sources, such as a microphone, CD player,
tuner, cassette player, or VCR. It is ruggedly
constructed for home or professional use.
The mixer’s many features give you almost
limitless sound combinations.
Its features include:
Eight Input Jacks — let you connect up to
two stereo input sources (such as a tuner,
cassette player, or CD player) or four mono
input sources, and up to four microphones.
Four Output Jacks — let you connect up to
two stereo output sources (such as an ampli-
fier or a cassette recorder) or four mono out-
put sources.
Four Wide-Range Sliding Controls — let
you adjust the sound level of the four chan-
nels to achieve the right mix for playing
through your speaker system or for record-
ing.
Stereo/Monaural Modes — let you select
either stereo or monaural output.
Dual Power Capability — lets you power
your mixer from either a 9-volt battery or from
an AC adapter.
Battery Low Indicator — lets you know
when the battery needs to be replaced.
ˆ Powering the Mixer
USING BATTERY POWER
Your can power the mixer with a 9-volt bat-
tery (not supplied). For the best results and
longest battery life, we recommend an alka-
line battery, available at your local Ra-
dioShack store.
1. Use a flat-blade screwdriver to loosen
the battery compartment cover's screw
and remove the cover.
WARNING: To reduce the risk of fire or
shock hazard, do not expose this product to rain
or moisture.
CAUTION
RISK OF ELECTRIC SHOCK.
DO NOT OPEN.
CAUTION: TO REDUCE THE RISK OF
ELECTRIC SHOCK, DO NOT REMOVE
COVER OR BACK. NO USER-SERVICE-
ABLE PARTS INSIDE. REFER SERVICING
TO QUALIFIED PERSONNEL.
This symbol is intended to alert
you to the presence of uninsu-
lated dangerous voltage within
the product’s enclosure that might
be of sufficient magnitude to con-
stitute a risk of electric shock. Do
not open the product’s case.
This symbol is intended to inform
you that important operating and
maintenance instructions are
included in the literature accom-
panying this product.
!
!
©2000 RadioShack Corporation.
All Rights Reserved.
RadioShack and RadioShack.com are trademarks used by RadioShack Corporation.

3
Preparation
2. Attach the bat-
tery snap in
the battery
compartment
to the 9-volt
battery's termi-
nals. Then
place the battery in the compartment.
3. Replace the cover and tighten the bat-
tery compartment cover's screw.
Replace the battery when the BATTERY
LOW indicator on the mixer's upper right cor-
ner lights.
USING AC POWER
You can power the mixer using an optional
9V AC adapter (not supplied).
Cautions:
You must use a Class 2 power
source that supplies 9V DC
and delivers at least 300 mA.
Its center tip must be set to negative and
its plug must fit the mixer’s DC 9V jack.
Using an adapter that does not meet
these specifications could damage the
mixer or the adapter.
• Always connect the AC adapter to the
mixer before you connect it to AC power.
When you finish, disconnect the adapter
from AC power before you disconnect it
from the mixer.
Follow these steps to connect the adapter.
1. Insert the AC adapter's barrel plug into
the DC 9V jack on the back of the mixer.
2. Plug the AC adapter's power module
into a standard AC outlet.
ˆ Preparation
PRESETTING THE
CONTROLS
Presetting the Mixer
Warning: A sudden high output from the
mixer could damage the audio devices con-
nected to the mixer and your hearing, espe-
cially if you use headphones.
To avoid accidentally overdriving a channel
or prematurely mixing in an audio input, ad-
just the mixer's controls to these settings be-
fore you turn on power.
!
DC 9V Jack
GND Terminal
Control Setting
POWER OFF
CHANNEL 1, 2, 3, 4 0 (Minimum)
MODE STEREO/
MONO MONO

4Preparation
Presetting the Audio Devices
To avoid sudden and unusable sound out-
puts from the audio devices connected to the
mixer's output, adjust the audio devices’ vol-
ume controls to minimum and set their power
controls to off before you connect the mixer's
output jacks to the audio devices' input jacks.
MAKING THE
CONNECTIONS
You can connect the line level outputs of
several input sources (such as a CD player,
a cassette player, the audio output of a VCR,
a tuner, or other input source) to the mixer.
The LINE input jacks let you connect up to
two stereo sources.
The MIC input jacks let you connect up to
four microphones.
Note: Use shielded audio cables for all con-
nections (available at your local RadioShack
store).
Connecting Two Stereo Inputs
To connect two stereo sources, use the two
pairs of LEFT and RIGHT phono input jacks
(for example, use LINE jacks 1(left) and 2
(right) for a CD player, and jacks 3(left) and
4(right) for a cassette player). The signals
for each of these sources are routed to the
corresponding output channel.
Connecting up to Four Stereo
Sources as Monaural Inputs
To connect up to four stereo sources as
monaural inputs, using shielded Y-adapters
at the sources' left and right outputs, connect
a separate stereo source to each channel
(LINE jacks 1through 4). The signals for each
of these sources are routed to the corre-
sponding output channel.
Connecting up to Four Monaural
Inputs
To connect up to four monaural sources, use
LINE jacks 1through 4 to connect a separate
POWER ON/OFF
MODE STEREO/MONO
CHANNEL 1, 2, 3, 4

5
Preparation
monaural source to each channel. The sig-
nals of each of these sources are routed to
the corresponding output channel.
Connecting Two Monaural
Sources as Stereo Inputs
To connect two monaural sources as two
stereo inputs, using shielded Y-adapters at
the sources' monaural outputs, connect the
other ends to the mixer's LEFT and RIGHT
channels (for example, connect one monau-
ral source to LINE jacks 1and 2, and a sec-
ond monaural source to LINE jacks 3and 4).
The signals for each of these sources are
routed to the corresponding output channel.
Connecting up to Four Micro-
phones
To connect up to four microphones, use MIC
jacks 1through 4. The signals for each of
these sources are routed to the correspond-
ing output channel.
Note: If you connect both LINE and MIC sig-
nal sources to the same channel, both sig-
nals are mixed and their levels are controlled
by the corresponding channel's fader control.
Connecting the Outputs
To play the mixer's output signal through
your speaker system (for events such as par-
ties, dances, conferences, etc.), connect one
end of an audio patch cord (not supplied) to
the mixer's OUTPUT LEFT and RIGHT jacks
and the other end of the audio patch cord to
your receiver/amplifier's microphone input
jacks.
To record the mixer's output signal, connect
one end of an audio patch cord (not sup-
plied) to the mixer's OUTPUT LEFT and RIGHT
jacks and the other end of the audio patch
cord to your tape deck's microphone input
jacks.
Notes:
• If you connect a PA system, attach a
ground wire between its ground terminal
(if it has one) and the mixer's GND termi-
nal.
• If you have a monaural PA system or
tape deck, use only one OUTPUT jack on
the mixer and set the mixer's MODE STE-
REO/MONO switch to MONO.
Amplifier

6Operation
ˆ Operation
After making all the necessary connections,
follow these steps to operate your mixer.
1. Set POWER ON/OFF to ON to turn on the
mixer.
Note: To avoid a possible popping
sound, always turn on the mixer before
you turn on the amplifier.
2. Turn on the output amplifier and leave
its volume set to minimum.
3. Set the selected audio input source's
volume to its minimum setting, turn it on,
and set it to play (or continuously talk
into the microphone).
4. Set the corresponding CHANNEL 1,
CHANNEL 2, CHANNEL 3, or CHANNEL 4
volume level to about 6 – 10.
Notes:
• When mixing more than one audio input
source, set all the volume level controls
of the audio input sources to the same
setting.
• Adjust the mixer's fader controls to get
the best mix. If the overall sound level is
too low with the fader controls at 10,
increase the output amplifier's volume.
5. Adjust the output amplifier's volume
level control to the desired volume.
6. When you are finished mixing, set
POWER ON/OFF to OFF and turn off the
output amplifier and all the audio input
sources.
MIXING MONO OR STEREO
When you set the mixer's MODE STEREO/
MONO switch to MONO:
• The mixer routes the input signal of any
monaural source connected to only one
of the mixer's line inputs (LEFT or RIGHT)
to both output channels.
• The mixer changes the stereo input sig-
nals connected to the mixer's line inputs
(LEFT and RIGHT) to monaural.
To mix mono signals with stereo signals, set
STEREO/MONO to STEREO.
Note: For mono amplifiers (found in some
PA systems), it is best to set MODE STEREO/
MONO to MONO.
VOICE-OVERS
You can mix an audio input source contain-
ing prerecorded music or special sounds
while you talk into a microphone. This lets
you mix your voice with music.
1. Set the mixer's fader controls for the
music source you want to mix to the
desired volume level (before you begin
talking).
2. While the music plays, talk into the
microphone and adjust the fader con-
trols for the microphone and music
source so you can hear yourself over
the music.
3. During pauses in speech, return the
music source's fader controls to their
original positions.
4. When you finish speaking,set the micro-
phone's fader control to 0and the music
source's fader controls to their original
positions.

7
Care
ˆ Care
Keep the mixer dry; if it gets wet, wipe it dry
immediately. Use and store the mixer only in
normal temperature environments. Handle
the mixer carefully; do not drop it. Keep the
mixer away from dust and dirt, and wipe it
with a damp cloth occasionally to keep it
looking new.
Modifying or tampering with the mixer’s inter-
nal components can cause a malfunction
and might invalidate its warranty. If your mix-
er is not performing as it should, take it to
your local RadioShack store for assistance.
ˆ Specifications
Input Sensitivity:
Mic ........................................................................................................................................................ 1 mV
Line ................................................................................................................................................... 100 mV
Output Level at 1 Kohm Load ............................................................................................................... 1 mV
Input Overload:
Mic ................................................................................................................................... More than 250 mV
Line .......................................................................................................................................... More than 6V
Distortion ............................................................................................................................. Less than 0.5%
Signal-to-Noise Ratio ....................................................................................................... Better than 55 dB
Frequency Response ................................................................................................. 20–20,000 Hz ± 2 dB
Power Requirements:
DC ........................................................................................................................................ One 9V Battery
AC (Using AC Adapter) ...................................................................................................... 120V AC, 60 Hz
Dimensions (HWD) ............................................................................................ 23/16 × 105/8× 65/16 Inches
(5.5 × 27.0 × 16.0 cm)
Weight ........................................................................................................................................ 2 lbs 4.3 oz
(930 g)
Specifications are typical; individual units might vary. Specifications are subject to change and improve-
ment without notice.

Cat. No. 32-1106
04A01
Printed in China
RadioShack Corporation
Fort Worth, Texas 76102
Limited One-Year Warranty
This product is warranted by RadioShack against manufacturing defects in material and workman-
ship under normal use for one (1) year from the date of purchase from RadioShack company-owned
stores and authorized RadioShack franchisees and dealers. EXCEPT AS PROVIDED HEREIN, Ra-
dioShack MAKES NO EXPRESS WARRANTIES AND ANY IMPLIED WARRANTIES, INCLUDING
THOSE OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE LIMITED
IN DURATION TO THE DURATION OF THE WRITTEN LIMITED WARRANTIES CONTAINED
HEREIN. EXCEPT AS PROVIDED HEREIN, RadioShack SHALL HAVE NO LIABILITY OR RE-
SPONSIBILITY TO CUSTOMER OR ANY OTHER PERSON OR ENTITY WITH RESPECT TO ANY
LIABILITY, LOSS OR DAMAGE CAUSED DIRECTLY OR INDIRECTLY BY USE OR PERFOR-
MANCE OF THE PRODUCT OR ARISING OUT OF ANY BREACH OF THIS WARRANTY, IN-
CLUDING, BUT NOT LIMITED TO, ANY DAMAGES RESULTING FROM INCONVENIENCE, LOSS
OF TIME, DATA, PROPERTY, REVENUE, OR PROFIT OR ANY INDIRECT, SPECIAL, INCIDEN-
TAL, OR CONSEQUENTIAL DAMAGES, EVEN IF RadioShack HAS BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.
Some states do not allow limitations on how long an implied warranty lasts or the exclusion or limita-
tion of incidental or consequential damages, so the above limitations or exclusions may not apply to
you.
In the event of a product defect during the warranty period, take the product and the RadioShack
sales receipt as proof of purchase date to any RadioShack store. RadioShack will, at its option, un-
less otherwise provided by law: (a) correct the defect by product repair without charge for parts and
labor; (b) replace the product with one of the same or similar design; or (c) refund the purchase
price. All replaced parts and products, and products on which a refund is made, become the prop-
erty of RadioShack. New or reconditioned parts and products may be used in the performance of
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original warranty period. You will be charged for repair or replacement of the product made after the
expiration of the warranty period.
This warranty does not cover: (a) damage or failure caused by or attributable to acts of God, abuse,
accident, misuse, improper or abnormal usage, failure to follow instructions, improper installation or
maintenance, alteration, lightning or other incidence of excess voltage or current; (b) any repairs
other than those provided by a RadioShack Authorized Service Facility; (c) consumables such as
fuses or batteries; (d) cosmetic damage; (e) transportation, shipping or insurance costs; or (f) costs
of product removal, installation, set-up service adjustment or reinstallation.
This warranty gives you specific legal rights, and you may also have other rights which vary from
state to state.
RadioShack Customer Relations, 200 Taylor Street, 6th Floor, Fort Worth, TX 76102
We Service What We Sell
12/99