32-2046.fm Page 1 Monday, January 24, 2000 12:33 PM
Cat. No. 32-2046
OWNER’S MANUAL
Please read before using this equipment.
50 Watt Speaker/Amplifier
MPS-50
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FEATURES
Your RadioShack MPS-50 50 Watt
Speaker/Amplifier is designed for use
with sound sources such as an electric
guitar, keyboard, or microphone. The
MPS-50 is portable, requiring only a flat
surface for setup, so you can use it to
practice or entertain at parties and gettogethers. Its full range 12-inch speaker
provides 50 watts RMS for optimum
sound quality.
Master Volume — lets you control the
MPS-50's overall output level.
Power On Indicator — lights to show
the MPS-50 is on.
Phones Jack — lets you connect a
mono headphone for private listening.
Line Out Jack — lets you connect a
power amplifier or mixer.
Your MPS-50 has these features:
Dual 1/4-Inch (6.35 mm) High and Low
Input Jacks — let you connect two keyboards, guitars, or high impedance microphones and two low impedance
(200–600 ohm) microphones.
Dual Gain, Bass, and Treble Controls — let you balance gain levels between the two channels and adjust the
low and high frequency response on
each channel.
Send and Return Jacks — let you connect a sound effect device (such as an
echo reverb or digital sampler processor).
Reverb Remote Jack — lets you connect a foot switch to control reverb effects.
Dual Reverb Switches — let you add
reverberation to either or both channels
to compensate for environmental conditions or to suit your personal preference.
Reverb Level Control — lets you control the amount of overall reverb.
Distortion Control — lets you select a
clean sound or add the desired amount
of distortion to match your musical style.
© 1999 Tandy Corporation.
All Rights Reserved.
RadioShack is a registered trademark used by Tandy Corporation.
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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-SERVICEABLE PARTS INSIDE. REFER SERVICING
TO QUALIFIED PERSONNEL.
This symbol is intended to alert
you to the presence of uninsulated dangerous voltage within
the product’s enclosure that might
be of sufficient magnitude to constitute a risk of electric shock. Do
not open the product’s case.
Cautions:
• To prevent electrical shock, any ACpowered equipment that you connect to the MPS-50 should be connected to a 3-prong (grounded) AC
outlet.
• To avoid damaging the MPS-50's
speaker, connect the sound source
to the MPS-50 first, then connect
the MPS-50 to power.
• Be sure to rotate MASTER to MIN
(minimum) before you connect the
MPS-50 to power, or before you
connect or disconnect an input
source to the MPS-50.
MASTER
MI
!
This symbol is intended to inform
you that important operating and
maintenance instructions are
included in the literature accompanying this product.
INPUT
GAIN
MI
HIGH
BASS
MA
MI
TREBLE
MA
MI
CHANNEL 1
INPUT
REVERB
GAIN
MA
MI
ON OFF
LOW
HIGH
BASS
MA
MI
TREBLE
MA
MI
REVERB
MA
REVERB
LEVEL
MI
MA
DISTORTION
OFF
MA
MA
MASTER
MI
MA
ON OFF
LOW
CHANNEL 2
POWER
3
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CONNECTIONS
INPUT
Note: You can connect audio equipment
with a stereo or monaural plug. When
you connect a stereo plug, the MPS-50
converts the stereo output to monaural.
Use a phone cable (available at your local RadioShack store) with a 1/4-inch
(6.35 mm) plug to connect an electric
guitar, keyboard, or high impedance microphone to the HIGH input jack of
Channel 1 and/or Channel 2.
Use a phone cable with a 1/4-inch (6.35
mm) plug to connect a low impedance
(200–600 ohms) microphone to the LOW
jack of Channel 1 and/or Channel 2.
To receive signal from the connected
device, connect a phone cable with a 1/4inch (6.35 mm) plug to the MPS-50’s
RETURN jack, then connect the other
end to the device’s output jack.
REVERB REMOTE
You can connect an optional remote
footswitch to the MPS-50’s REVERB REMOTE jack and use the switch to control
reverb effects.
PHONES
CAUTION
CAUTION
LINE
OUT
RETURN
DISCONNECT SUPPLY CORD BEFORE CHANGING
FOR CONTINUED PROTECTION AGAINST RISK OF FIRE REPLACE
ONLY
REVERB
REMOTE
CAT. NO. 32-2046
~120V AC 60Hz
150W
MPS-50
GUITAR AMPLIFIER
POWER SUPPLY: ~120V 60Hz 150W (FUSE 2A
250V)
Custom Manufactured in China
for RadioShack , A Division of Tandy
Corporation, Fort Worth, TX 76102
POWER
PHONES
CAUTION
SEND
LINE
OUT
RETURN
COMMERCIAL AUDIO
EQUIPMENT
115703
SEND
REVERB
REMOTE
FUSE 2A
250V
CAUTION
RISK OF ELECTRIC
DO NOT OPEN
TO PREVENT ELECTRIC SHOCK DO NOT USE THIS (POLARIZED) PLUG WITH AN EXTENSION CORD
RECEPTACLE
OUTPUT
To play the MPS-50's output signal
through your sound system, connect
one end of an audio patch cord (available at your local RadioShack store)
with a 1/4-inch (6.35 mm) phone plug to
the MPS-50's LINE OUT jack. Then connect the other end to your amplifier/receiver/mixer's input jack.
POWER
Note: Before you connect the MPS-50
to AC power, set POWER to the off (out)
position and MASTER to MIN.
Connect the female jack end of the supplied power cord to the AC jack on the
back of the MPS-50, then connect the
other end to a standard AC outlet.
SEND AND RETURN
To send the MPS-50's signal to a sound
effect device, such as an echo reverb or
digital sampler processor, connect a
phone cable (available at your local RadioShack store) with a 1/4-inch (6.35 mm)
plug to the MPS-50’s SEND (output)
jack, then connect the other end to the
sound effect device’s input jack.
4
CAUTION
CAUTION
DISCONNECT SUPPLY CORD BEFORE CHANGING
FOR CONTINUED PROTECTION AGAINST RISK OF FIRE REPLACE
ONLY
CAT. NO. 32-2046
~120V AC 60Hz
150W
MPS-50
GUITAR AMPLIFIER
POWER SUPPLY: ~120V 60Hz 150W (FUSE 2A
250V)
Custom Manufactured in China
for RadioShack , A Division of Tandy
Corporation, Fort Worth, TX 76102
POWER
PHONES
CAUTION
RISK OF ELECTRIC
DO NOT OPEN
LINE
OUT
FUSE 2A
250V
CAUTION
TO PREVENT ELECTRIC SHOCK DO NOT USE THIS (POLARIZED) PLUG WITH AN EXTENSION CORD
RECEPTACLE
RETURN
COMMERCIAL AUDIO
EQUIPMENT
115703
SEND
REVERB
REMOTE
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OPERATION
USING HEADPHONES
INPUT
GAIN
MI
HIGH
INPUT
BASS
MA
MI
GAIN
MA
MI
LOW
HIGH
GAIN
MI
HIGH
MI
TREBLE
MA
MI
CHANNEL 1
INPUT
REVERB
GAIN
MA
MI
ON OFF
LOW
MI
MA
CHANNEL 2
BASS
MA
MA
LOW
CHANNEL 1
INPUT
BASS
HIGH
BASS
MA
MI
TREBLE
MA
MI
REVERB
MA
REVERB
LEVEL
MI
MA
DISTORTION
OFF
MA
MAS
To listen privately, connect low-impedance headphones (available at your local RadioShack store) with a 1/4-inch
(6.35 mm) phone plug to the PHONES
jack on the back of the MPS-50.
MI
ON OFF
LOW
CHANNEL 2
PHONES
1. Rotate MASTER to MIN.
2. Press POWER up to turn on the
MPS-50. The POWER indicator
lights.
CAUTION
CAUTION
DISCONNECT SUPPLY CORD BEFORE CHANGING
FOR CONTINUED PROTECTION AGAINST RISK OF FIRE REPLACE
ONLY
• Rotate GAIN clockwise toward
MAX to increase the volume, or
counterclockwise toward MIN to
reduce it.
• Rotate BASS clockwise toward
MAX to increase the low frequency sounds, or counterclockwise toward MIN to reduce them.
• Rotate TREBLE clockwise toward
MAX to increase the high frequency sounds, or counterclockwise toward MIN to reduce them.
• Rotate DISTORTION until you hear
the amount of distortion you want.
• Press REVERB in on each channel where you want to apply
reverb effects. Then rotate
REVERB LEVEL toward MAX to
increase the amount of reverb, or
toward MIN to lower it.
GUITAR AMPLIFIER
MPS-50
POWER SUPPLY: ~120V 60Hz 150W (FUSE 2A
250V)
Custom Manufactured in China
for RadioShack , A Division of Tandy
Corporation, Fort Worth, TX 76102
PHONES
CAUTION
RISK OF ELECTRIC
DO NOT OPEN
3. Adjust the sound for each channel
where you have connected an input
source.
CAT. NO. 32-2046
~120V AC 60Hz
150W
POWER
LINE
OUT
RETURN
COMMERCIAL AUDIO
EQUIPMENT
R
115703
SEND
REVERB
REMOTE
FUSE 2A
250V
CAUTION
TO PREVENT ELECTRIC SHOCK DO NOT USE THIS (POLARIZED) PLUG WITH AN EXTENSION CORD
RECEPTACLE
Listening Safely
To protect your hearing, follow these
guidelines when you use headphones.
• Set the volume to the lowest setting
before you begin listening. After you
begin listening, adjust the volume to
a comfortable level.
• Do not listen at extremely high volume levels. Extended high-volume
listening can lead to permanent
hearing loss.
• Once you set the volume, do not
increase it. Over time, your ears
adapt to the volume level, so a volume level that does not cause discomfort might still damage your
hearing.
4. To turn the MPS-50 off, press
POWER down.
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CARE
To enjoy your MPS-50 for a long time:
• Keep the MPS-50 dry. If it gets wet,
wipe it dry immediately.
• Use and store the MPS-50 only in
normal temperature environments.
• Handle the MPS-50 gently and carefully. Don’t drop it.
• Keep the MPS-50 away from dust
and dirt.
• Wipe the MPS-50 with a damp cloth
occasionally to keep it looking new.
Modifying or tampering with the MPS50’s internal components can cause a
malfunction and invalidate its warranty.
If your MPS-50 is not performing as it
should, take it to your local RadioShack
store for assistance.
REPLACING THE FUSES
If the MPS-50 does not operate, the
power fuse under the AC socket on the
rear panel or the internal suppy fuses on
the printed circuit board might have
blown. If this happens, replace the fuses
with new ones of the same type, available at your local RadioShack store.
6
Power fuse
2 Amp 250V, slow blow
Internal supply fuse
3.5 Amp 250V, slow
blow
Important Notes:
• Let the MPS-50 cool down and see
if it starts again before you assume
a fuse needs to be replaced.
• Because the internal supply fuse is
located on the printed circuit board,
we strongly recommend that you
take it to your local RadioShack
store rather than attempting to
replace it yourself.
Caution: Do not use a fuse with ratings
other than those specified here. Doing
so might damage your MPS-50.
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SPECIFICATIONS
Input Impedance .................................................................... 15K Ohms (High Level)
3K ohms (Low Level)
Output Power, 1% T.H.D., 4 Ohms Load, 1 kHz ........................................... 50 Watts
10% T.H.D. 4 Ohm Load, 1 kHz .................................................................... 65 Watts
Line Out (High 50 mV Input), 2 kHz ................................................................ 500 mV
Send Out (High 50 mV Input), 2 kHz .............................................................. 500 mV
T.H.D. at 2 kHz 2w ............................................................. 0.2% High and Low Level
Input Sensitivity, 2 kHz at 50 Watts Output .................................. 50 mV (High Level)
5 mV (Low Level)
S/N Ratio (A-Weighted) ................................................................ 70 dB (High Level)
60 dB (Low Level)
Frequency Response 0 dB = 2W (2 kHz) .................... 100 Hz –10 dB, 10 kHz +5 dB
High and Low Level
Tone Control, Bass, 100 Hz ............................................. +8 dB (Max.) –11 dB (Min.)
Tone Control, Treble, 10k Hz ........................................... +8 dB (Max.) –11 dB (Min.)
Return In 2 kHz 50 Watts Output .................................................................... 500 mV
Delay Time ...................................................................................................... 150 mS
Noise Level ......................................................................................................... 2 mV
Power Requirement .......................................................................... AC 120 V/60 Hz
Speaker ............................................................................................ 12-Inch, 4 Ohms
Dimensions (HWD) ................................................................ 181/2 × 161/3 × 11 Inches
(470 × 415 × 280 mm)
Weight ................................................................................................................ 34 lbs
(15.04 kg)
Specifications are typical; individual units might vary. Specifications are subject to
change and improvement without notice.
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Limited Ninety-Day Warranty
This product is warranted by RadioShack against manufacturing defects in material and workmanship under normal use for ninety (90) days from the date of purchase from RadioShack companyowned stores and authorized RadioShack franchisees and dealers. EXCEPT AS PROVIDED
HEREIN, RadioShack 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 RESPONSIBILITY TO CUSTOMER OR ANY OTHER PERSON OR ENTITY WITH RESPECT TO ANY LIABILITY, LOSS OR DAMAGE CAUSED DIRECTLY OR INDIRECTLY BY USE
OR PERFORMANCE OF THE PRODUCT OR ARISING OUT OF ANY BREACH OF THIS WARRANTY, INCLUDING, BUT NOT LIMITED TO, ANY DAMAGES RESULTING FROM INCONVENIENCE, LOSS OF TIME, DATA, PROPERTY, REVENUE, OR PROFIT OR ANY INDIRECT,
SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, EVEN IF RadioShack HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
Some states do not allow the limitations on how long an implied warranty lasts or the exclusion 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, unless 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 property of RadioShack. New or reconditioned parts and products may be used in the performance of
warranty service. Repaired or replaced parts and products are warranted for the remainder of the
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
04/99
RadioShack
A Division of Tandy Corporation
Fort Worth, Texas 76102
08A99
Printed in China