Optimus 32-3009 User manual

Cat. No. 32-3009
OWNER’S MANUAL
Please read before using this equipment.
SSM-1250
3-Channel Stereo Audio Mixer
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2
This symbol is intended to alert you to the presence of uninsulated dan-
gerous voltage within the mixer’s enclosure that might be of sufficient
magnitude to constitute a risk of electric shock. Do not open the mixer’s
case.
This symbol is intended to inform you that important operating and main-
tenance instructions are included in the literature.
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.
Warnin
g
: To prevent fire or shock
hazard, do not expose this mixer to
rain or moisture.
CAUTION !
!
© 1997 Tandy Corporation.
All Rights Reserved.
RadioShack and Optimus are registered trademarks used by Tandy Corporation.
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CONTENTS
Features ................................................................................................................ 4
Preparation ........................................................................................................... 6
Connecting the Outputs .................................................................................. 6
Connecting the Inputs ..................................................................................... 6
Connecting Power ........................................................................................... 8
Connecting a Lamp ......................................................................................... 8
Connecting Headphones ................................................................................ 9
Listening Safely ........................................................................................ 9
Operation ............................................................................................................ 10
Presetting the Input Signal Levels ................................................................ 10
Presetting the Microphone ...................................................................... 11
Presetting the Channel 1/2/3 Input Sources ........................................... 11
Checking the Sound ............................................................................... 14
Mixing the Inputs ........................................................................................... 15
Playing One Input Source ....................................................................... 15
Monitoring a Second Input Source ......................................................... 15
Switching to the Second Input Source .................................................... 16
Notes on Mixing ...................................................................................... 16
Using Talkover .............................................................................................. 17
Using the Tone Controls ................................................................................ 18
Troubleshootin
g
................................................................................................ 19
Care and Maintenance ...................................................................................... 20
Replacing the Fuse ....................................................................................... 21
Specifications .................................................................................................... 22
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FEATURES
Your Optimus SSM-1250 3-Channel Stereo Audio Mixer is a sophisticated control
center, perfect for mixing sound from multiple audio sources on three separate
channels such as microphones, tuners, CD players, turntables, or the audio out-
puts from VCRs. The mixer is ruggedly constructed for home or professional use.
Its wide-range volume controls let you adjust each audio source’s sound level so
you can get the best mix for playing through your sound system or for recording.
1DJ Microphone Input — lets you
connect a balanced, low imped-
ance microphone with an XLR
plug.
2 Microphone Treble — lets you
adjust the microphone’s treble.
3 Microphone Bass — lets you ad-
just the microphone’s bass.
4 Assi
g
n Controls — lets you se-
lect the input sources to be mixed.
5 Talkover — lowers the sound of
the input sources so you can talk
over them using the microphone.
6 Slide Volume Controls — for fin-
gertip control of sound mixing and
fading.
7 Cross Fader — lets you smoothly
switch between two input sources.
8 Input Source Selectors — let
you easily choose the desired au-
dio input source to be played.
9 Master Volume — lets you con-
trol the mixer’s overall volume lev-
el.
10 Output Level VU Meters — indi-
cate the mixer’s total output signal
level.
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5
11 Mono/Stereo Selector — lets
you set the output to stereo or
monaural.
12 Bass/Middle/Treble Controls —
let you adjust the tone of the se-
lected output to get just the right
sound.
13 Cue Assign Controls — lets you
select the channel where the de-
sired audio input source is located
so you can monitor and prepare it
before mixing it in.
14 Cue/Program Control — lets you
balance the volume of the output
playing on the sound system and
the input being prepared for mix-
ing through the headphones.
15 Lamp Jack — lets you connect a
12V DC lamp to light the mixer
controls.
16 Phones Jack — lets you connect
a pair of stereo headphones with
a 1/4-inch plug.
17 Cue Level — lets you adjust the
headphone’s volume level.
18 Stereo Line Outputs — let you
connect the mixer’s output to your
receiver/amplifier and tape deck
so you can play the sounds from
your input sources through your
speaker system, and record them.
19 Stereo Line Inputs — let you
connect most line-level audio
sources such as a CD player, tape
deck, tuner, camcorder, or VCR.
20 Stereo Phono Inputs — for con-
necting low-level audio sources,
such as turntables with a magnet-
ic cartridge.
21 Microphone Input — lets you
connect a low impedance micro-
phone with a 1/4-inch plug instead
of one with an XLR plug.
illustration of mixer back
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6
PREPARATION
Warnin
g
: A sudden high output from
the mixer could damage your hearing,
especially if you use headphones, and
might also damage the audio devices
connected to the mixer’s output. Be-
fore using the mixer, make sure you
set your receiver/amplifier’s volume
control to its minimum volume level
setting.
Before you connect the AC power
cord, make sure you set POWER to off.
And, to avoid sudden and unusable
sound outputs from any audio devices
that you connect to the mixer, be sure
to have their power controls set to off
(and any tone controls set to flat).
CONNECTING THE
OUTPUTS
To play the mixer’s output signal
through your sound system (for events
such as parties, dances, conferences,
and so on), connect one end of an au-
dio patch cord (Cat. No. 42-2356, not
supplied) to the mixer’s AMP L(white)
and R(red) output jacks, then connect
the other end to your receiver/amplifi-
er’s left and right line input jacks
(matching left to left, and right to right).
To record the mixer’s output signal,
connect one end of an audio patch
cord (Cat. No. 42-2356, not supplied)
to the mixer’s REC L(white) and R
(red) output jacks, then connect the
other end to your tape deck’s left and
right line input jacks (matching left to
left, and right to right).
CONNECTING THE
INPUTS
You can connect up to four line-level
and up to two low-level audio input
sources to the input jacks on the back
of the mixer. You can also connect a
microphone to the mixer’s front or
back panel.
illustration of output AMP
to sound system
illustration of output REC
to recorder
AMP connections should
still appear
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7
1. Connect the line-level outputs from up to four audio sources (such as a CD
player, tape deck, tuner, camcorder, or VCR) to the LINE 1, LINE 2, LINE 3, and
LINE 4 input jacks (matching left to left, right to right).
Caution: Do not connect an audio source with a line-level output to the low-
level PHONO 1 or PHONO 2 input jacks.
2. Connect the low-level outputs from up to two audio sources (such as magnetic-
cartridge turntables) to the PHONO 1 and PHONO 2 input jacks (matching left to
left, right to right).
Note: If you connect magnetic-cartridge turntables, also connect their ground
wires (usually black or green) to GND.
illustration of line-level
connections
AMP and REC connections
should also appear
illustration of low-level
connections
AMP, REC, and line-level
connections should also
appear
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8
3. Connect a microphone (not sup-
plied) to the mixer.
• If the microphone has an XLR
plug, connect it to MIC on the
top left corner of the front panel.
• If the microphone has a 1/4-inch
plug,connectittoMIConthelow-
er right corner of the back panel.
Note: We recommend you do not
connect an XLR and a 1/4-inch
plug microphone to the mixer at
the same time.
CONNECTING POWER
Connect the power cord to a standard
AC outlet.
Note: The power cord has a polarized
plug that fits only one way into a stan-
dard AC outlet. If the plug does not fit,
turn it clockwise so it fits properly. Do
not force the plug into the AC outlet or
you could damage the outlet or the
plug.
CONNECTING A LAMP
The mixer has a 12V BNC lamp sock-
et for connecting a 12V DC/3W lamp
(RSU Cat. No. 11443363) so you can
see the control panel in dark or low-
light conditions.
Caution: Use only a 12V DC/3W
lamp.
illustration of microphone
plug being inserted into jack
Do not show entire
microphone
illustration of microphone
plug being inserted into jack
Do not show entire
microphone illustration of lamp
being connected
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9
CONNECTING
HEADPHONES
To listen in privacy or monitor the au-
dio source inputs so you can locate an
exact passage or section before mix-
ing it, plug a pair of stereo head-
phones (not supplied) with a 1/4-inch
plug into the PHONES jack on the mix-
er’s right front panel.
Your local RadioShack store carries a
wide selection of headphones.
Listening Safely
Do not listen at extremely high volume
levels. Extended high-volume listening
can lead to permanent hearing loss.
To protect your hearing when you use
headphones, always follow these
guidelines to set the listening volume.
•Set
CUE LEVEL to the lowest set-
ting before you begin listening.
• After you put on the headphones,
adjust CUE LEVEL to a comfort-
able listening volume level.
• Once you set your headphones’
volume, do not increase it. Over
time, your ears adapt to the vol-
ume level, so a level that no
longer causes discomfort might
still damage your hearing.
illustration of headphones
being connected
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10
OPERATION
1. Set the volume levels on the out-
put devices (receiver/amplifier and
tape deck) to minimum and turn
them on.
2. Press POWER to turn on the mix-
er. The red power indicator lights.
3. Turn on the input sources you
want to mix.
4. Using the mixer requires two basic
operations:
• Presetting the input signal lev-
els (see “Presettiing the Input
Signal Levels”)
• Mixing the audio input sources
(see “Mixing the Inputs” on
Page 15)
5. After you finish mixing, turn down
the volume on the output audio
devices, turn off the input and out-
put audio devices (amplifiers, tape
decks, and so on), then press
POWER so it pops up to turn off
the mixer. The power indicator
turns off.
illustration of POWER
button w/indicator lit
PRESETTING THE INPUT
SIGNAL LEVELS
To avoid accidentally overdriving a
channel or prematurely mixing in an
audio input source, make sure you
start with the following settings:
• Volume slide controls set to 0
•ASSIGN A and ASSIGN B set to
OFF
•MIC TREBLE, MIC BASS, CUE LEV-
EL, TREBLE, MID, BASS, and
MASTER set to 0
illustration
illustration
illustration
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11
Rotate MASTER clockwise and tempo-
rarily set it to about the 5th marker.
Note: The MASTER volume control
adjusts the overall volume of DJ MIC,
CH1, CH2, and CH3.
The mixer uses two volume unit (VU)
meters to indicate the total stereo out-
put signal level. For the best results,
each input signal level should normal-
ly be set so the VU meters never
move into the red range (0or above).
Distortion is likely to occur on audio
peaks if the meter moves into the red
range.
For monaural output, set MONO/STE-
REO to MONO. For stereo output, set
MONO/STEREO to STEREO.
Presetting the Microphone
1. If your microphone has an ON/
OFF control, set it to ON.
2. Set OFF/ON/TALKOVER to ON.
3. While continuously talking, adjust
DJ MIC until you get a reading of
up to 0on both VU meters.
4. Set OFF/ON/TALKOVER to OFF.
Presetting the Channel 1/2/3
Input Sources
Before you mix channels 1, 2, and 3,
you must preset the input signal level
for each channel input source (up to
six sources).
illustration
illustration of VU meters
at 0
illustration of mixer front
w/arrow to control
illustration
illustration DJ MIC
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12
If you did not connect an input source
to every jack or do not want to mix ev-
ery input source connected to the mix-
er’s input jacks, you do not need to
follow all the steps in this section. Af-
ter you decide which source(s) you
want to preset and mix, use this table
to determine which steps to follow.
Notes:
• While you adjust the input signal
levels for channels 1, 2, and 3, ei-
ther use the headphones or turn
up the receiver/amplifier’s volume
to a comfortable listening level
(not necessarily the final usable
level).
• Do not play a quiet portion of mu-
sic while you adjust the volume
levels, otherwise the volume lev-
els for channels 1, 2, and 3 will be
overdriven during the loud por-
tions of the music.
To Preset See Steps
Channel 1 Phono 1 1–4
Line 1 5
Channel 2 Phono 2 6–9
Line 2 10
Channel 3 Line 3 11–14
Line 4 15
1. To preset the PHONO 1 input
source, set PHONO 1/LINE 1 to
PHONO 1.
2. Start playback of the selected in-
put source.
3. Slowly slide up the CH 1 volume
level slide control until you get a
reading of up to 0on both VU
meters.
Important: Write down or remem-
ber the CH 1 volume level slide
control’s setting for the selected
audio source, so each time you
want to mix that source you can
slide the CH 1 volume level slide
control to the correct setting.
Note: If it was necessary to set
the
CH 1 volume level slide control
all the way to 10 in order to get a
reading of up to 0on the VU
meter, then slide CH 1 down to
about
8and rotate MASTER clock-
wise until you get the reading of 0
on the VU meters.
illustration of
PHONO 1/LINE 1 set
to PHONO 1
illustration of CH 1 control
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13
4. Stop playback of the selected in-
put source.
5. To preset the LINE 1 input source,
set PHONO 1/LINE 1 to LINE 1.
Then repeat Steps 2–4.
Note: If you have to readjust MAS-
TER when performing Step 3, re-
member that this affects the level
of the previously preset input
sources. You must readjust those
sources until you get a reading of
up to 0on the VU meters for each.
6. To preset the PHONO 2 input
source, set PHONO 2/LINE 2 to
PHONO 2.
7. Start playback of the selected in-
put source.
8. Slowly slide up the CH 2 volume
level slide control until you get a
reading of up to 0on both VU
meters.
illustration of
PHONO 2/LINE 2 set
to PHONO 2
illustration of CH 2 control
Im
p
ortant: Write down or remem-
ber the CH 2 volume level slide
control’s setting for the selected
audio source, so each time you
want to mix that source you can
slide the CH 2 volume level slide
control to the correct setting.
Note: If it was necessary to set
the
CH 2 volume level slide control
all the way to 10 in order to get a
reading of up to 0on the VU
meter, then slide CH 2 down to
about
8and rotate MASTER clock-
wise until you get the reading of 0
on the VU meters.
9. Stop playback of the selected in-
put source.
10. To preset the LINE 2 input source,
set PHONO 2/LINE 2 to LINE 2.
Then repeat Steps 7–9.
Note: If you have to readjust MAS-
TER when performing Step 8, re-
member that this affects the level
of the previously preset input
sources. You must readjust those
sources until you get a reading of
up to 0on the VU meters for each.
11. To preset the LINE 3 input source,
set LINE 3/LINE 4 to LINE 3.
12. Start playback of the selected in-
put source.
illustration of
LINE 3/LINE 4 set to
LINE 3
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14
13. Slowly slide up the CH 3 volume
level slide control until you get a
reading of up to 0on both VU
meters.
Im
p
ortant:
Write down or remem-
ber the CH 3 volume level slide
control’s setting for the selected
audio source, so each time you
want to mix that source you can
slide the CH 3 volume level slide
control to the correct setting.
Note: If it was necessary to set
the CH 3 volume level slide control
all the way to 10 in order to get a
reading of up to 0on the VU
meter, then slide CH 3 down to
about
8and rotate MASTER clock-
wise until you get the reading of 0
on the VU meters.
14. Stop playback of the selected in-
put source.
15. To preset the LINE 4 input source,
set LINE 3/LINE 4 to LINE 4. Then
repeat Steps 12–14.
Note: If you have to readjust MAS-
TER when performing Step 13, re-
member that this affects the level
of the previously preset input
sources. You must readjust those
sources until you get a reading of
up to 0on the VU meters for each.
illustration of CH 3 control
16. To prevent prematurely mixing au-
dio sources, set all volume level
slide controls to 0.
Checking the Sound
1. Select one of the input sources,
then start playback of the selected
source.
2. Set the volume level slide control
to the position you determined
during presetting. The VU meters
should show a reading of up to 0
dB.
3. Turn up the receiver/amplifier’s
volume until it reaches the desired
level for the location or event
where the mixer will be used (this
can vary).
4. Adjust BASS, MID, and TREBLE to
get the desired sound (see “Using
the Tone Controls” on Page 18).
Note: If adjusting BASS, MID, and
TREBLE causes the VU meters to
exceed 0dB, rotate MASTER
counterclockwise until the read-
ing returns to 0. Then adjust your
output device (amplifier) volume
accordingly.
5. Stop playback of the selected in-
put source.
Note: Do not adjust MASTER after
checking the sound.
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15
MIXING THE INPUTS
You can connect input signals from up
to six audio sources, select any two,
then mix them so only one or both
play through your sound system.
Mixing requires three operations:
• Playing one input source
• Monitoring the next input source
• Switching to the next input source
You can play either of the two select-
ed sources first.
Notes:
• Ensure the volume level slide con-
trol for the other input channel
source is set to 0.
• The CUE ASSIGN switches are
push-on and push-off. You can se-
lect more than one at a time.
Playing One Input Source
1. Set ASSIGN A to the desired
source, then set CROSS FADER to
A.
illustration of ASSIGN A
set to 1 and CROSS
FADER set to A
2. Set the input source selector to
the preset input source you want
to play first through your sound
system.
3. Make sure the first input source’s
volume level slide control is set to
the correct preset position.
4. Start playback of the input source.
Monitoring a Second
Input Source
Monitoring a second input source’s
signal level requires selecting the in-
put source that is
not
currently play-
ing, finding the desired section you
want to mix, then adjusting that
source’s sound level so it matches the
volume level of the source currently
playing.
1. Connect and put on headphones.
Note: You can listen to one chan-
nel through the headphones while
the other channel is playing
through the sound system.
2. Set ASSIGN B to the second input
source.
illustration
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16
3. Press CUE ASSIGN for the second
input source.
4. Set the input source selector to
the input source you want to mon-
itor.
5. Start playback of the input source
you want to play next through your
sound system.
6. If necessary:
• Adjust CUE LEVEL to a comfort-
able listening level.
• Adjust the second input source
volume slide control to the cor-
rect preset position.
7. Set the input device to the desired
section of music, then stop or
pause the input device.
Switching to the Second
Input Source
1. Start playback of the second input
source.
2. When you are ready to play its
sound through your sound sys-
illustration of CUE
ASSIGN with arrow to
CH 2
illustration
tem, slide CROSS FADER from A
to B.
Slide CROSS FADER:
• To the
left
to fade in the channel
selected by ASSIGN A and fade
out the channel selected by AS-
SIGN B.
• To the
right
to fade in the chan-
nel selected by ASSIGN B and
fade out the channel selected
by
ASSIGN A.
• To the
center
to equally mix the
two.
Notes on Mixing
• If you set CROSS FADER to A to
play the channel selected by AS-
SIGN A, then you must set CUE
ASSIGN
to
CH 1 tomonitor CH 1, to
CH 2 to monitor CH 2, to CH 3 to
monitor CH 3, to CH 4 to monitor
CH 4, and to MIC to monitor DJ
MIC. The same applies when you
set CROSS FADER to B.
• To mix any two inputs selected by
the ASSIGN switches, set each
ASSIGN switch to the desired
channel. Then use CROSS FADER
to mix the two.
illustration of CROSS
FADER w/arrow
from A to B
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17
• Do not slide CROSS FADER to the
center if you want to
monitor
one
channel while the other is playing.
Otherwise, the sound from the
channel you monitor will also be
heard through your sound system.
Instead, slide CROSS FADER to
the channel you are not monitor-
ing. For example, to monitor chan-
nel 1 (selected by ASSIGN A)
while channel 2 (selected by AS-
SIGN B) is playing, slide CROSS
FADER to B.
•Use
CUE/PGM to listen to the input
controlled by the CUE ASSIGN
switch and what is playing on the
currently selected output device.
When
CUE/PGM is set to CUE, you
only hear the channel selected by
the CUE ASSIGN switches. When
CUE/PGM is set to PGM, you only
hear what is playing on the cur-
rently selected output device. Ro-
tate CUE/PGM to listen to both
inputs at the same time.
USING TALKOVER
When you are not using the micro-
phone, leave OFF/ON/TALKOVER set
to OFF. The microphone’s input is
turned off and all other audio input
sources are unaffected.
If you want to use a microphone:
•Set
OFF/ON/TALKOVER to ON to
mix the microphone equally with
the other audio input sources.
•Set
OFF/ON/TALKOVER to TALK-
OVER
to mix the microphone at a
higher level than the other audio
input sources.
Your voice sounds clearly through
the microphone, but all the other
audio input sources sound at a
lower level. (This is useful for pag-
ing.)
illustration of switch
set to TALKOVER
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18
USING THE TONE
CONTROLS
Your mixer has one set of tone con-
trols for the microphone and another
set for channels 1, 2, and 3. You can
tailor the high and low frequency
sounds for the microphone and tailor
the high, low, and mid frequency
sounds for channels 1, 2, and 3.
For normal sound, leave BASS, MID,
and TREBLE (or MIC BASS and MIC
TREBLE for the microphone) set to 0.
Rotate TREBLE (or MIC TREBLE) to-
ward +10 to increase, or toward –10 to
decrease the high frequency sounds.
Rotate MID toward +10 to increase or
toward –10 to decrease the middle fre-
quency sounds.
Rotate BASS (or MIC BASS) toward
+10 to increase or toward –10 to de-
crease the low frequency sounds.
illustration of mixer front
w/arrows to the control
locations
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19
TROUBLESHOOTING
With proper care and handling, your mixer should give you years of trouble-free
service. However, if your SSM-1250 is not working properly, follow these sugges-
tions to see if you can eliminate the problem. If you cannot, take the mixer to your
local RadioShack store for assistance.
Problem Possible Solution
Nothing works Check the AC power connection and make sure the AC
outlet is “live.”
Check all the connections to the system (amplifier/
receiver, input sources, and so on).
Check the fuse. See “Replacing the Fuse” on Page 21.
No signal from an audio
input source Make sure the OFF/ON/TALKOVER switch is not set to
TALKOVER.
Check the mixer’s and the source’s control settings.
Check the connection between the mixer and the input
source.
Hum from PHONO
sources Make sure the turntable’s ground wire (usually black or green) is connected to the GND screw on the back of
the mixer.
Hum from other input
sources Make sure there are no low-level inputs connected to the LINE input jacks.
Feedback “squeals” Move the microphone further away from the output
speakers or use a unidirectional microphone.
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20
CARE AND MAINTENANCE
Your Optimus SSM-1250 3-Channel Stereo Audio Mixer is an example of superior
design and craftsmanship. The following suggestions will help you care for your
mixer so you can enjoy it for years.
Keep the mixer dry. If it gets wet, wipe it dry immediately. Liquids
might contain minerals that can corrode the electronic circuits.
Use and store the mixer only in normal temperature environments.
Temperature extremes can shorten the life of electronic devices and
distort or melt plastic parts.
Keep the mixer away from dust and dirt, which can cause premature
wear of parts.
Handle the mixer gently and carefully. Dropping it can damage circuit
boards and cases and can cause the mixer to work improperly.
Wipe the mixer with a damp cloth occasionally to keep it looking new.
Do not use harsh chemicals, cleaning solvents, or strong detergents
to clean the mixer.
Modifying or tampering with the mixer’s internal components can cause a mal-
function and might invalidate your mixer’s warranty. If your mixer is not performing
as it should, take it to your local RadioShack store for assistance.
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