STAGE RIGHT SB20 50-watt Guitar Manual

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STAGE RIGHT SB20 50-watt Guitar

STAGE RIGHT SB20 50-watt Guitar 


Please read this entire manual before using this device, paying extra attention to these safety warnings and guidelines. Please keep this manual in a safe place for future reference.

  • This device is intended for indoor use only.
  • Do not expose this device to water or moisture of any kind. Do not place drinks or other containers with moisture on or near the device. If moisture does get in or on the device, immediately remove it from its power source and allow it to fully dry before reapplying power.
  • Do not touch the device, the power cord, or any other connected cables with wet hands.
  • Do not expose this device to excessively high temperatures. Do not place it in, on, or near a heat source, such as a fireplace, stove, radiator, etc. Do not leave it in direct sunlight.
  • Do not place or install this device in an area where it can be exposed to excessive amounts of dust, humidity, oil, smoke, or combustible vapors.


  • Prior to operation, check the unit and power cord for physical damage. Do not use if physical damage has occurred.
  • Before plugging the unit into a power outlet, ensure that the outlet provides the same type and level of power required by the device.
  • This device uses a grounded power cord and requires a ground connection for safe operation. Ensure that the power source has a proper ground connection. Do not modify the plug or use a “cheater” plug to bypass the ground connection.
  • Disconnect the unit from the power source when replacing the fuse. Replace the fuse only with one of the types shown in the specifications.
  • Unplug this device from the power source when not in use.
  • Take care to prevent damage to the power cord. Do not allow it to become crimped, pinched, walked on, or become tangled with other cords. Ensure that the power cord does not present a tripping hazard.


The Monoprice Customer Service department is dedicated to ensuring that your ordering, purchasing, and delivery experience is second to none. If you have any problem with your order, please give us an opportunity to make it right. You can contact a Monoprice Customer Service representative through the Live Chat link on our website or via email at Check the website for support times and links.


Please take an inventory of the package contents to ensure you have all the items listed below. If anything is missing or damaged, please contact Monoprice Customer Service for a replacement.

  • 1x SB-20 Guitar Amp Head
  • 1x AC Power Cord
  • 1x User’s Manual


Front Panel

STAGE RIGHT SB20 50-watt Guitar  FIG 1

  1. POWER: Turns the amplifier on or off.
  2. STANDBY: Turns standby mode on or off.
  3. INDICATOR: Illuminates when the amp is powered on.
  4. MASTER VOLUME: Adjusts the volume level of the reverb effect for both channels.
  5. MASTER REVERB: Adjusts the amount of reverb to add to the overall signal.
  6. CLEAN BASS: Adjusts the low-frequency response for the CLEAN channel.
  7. CLEAN MIDDLE: Adjusts the middle-frequency response for the CLEAN channel.
  8. CLEAN TREBLE: Adjusts the high-frequency response for the CLEAN channel.
  9. CLEAN BRIGHT: Turns high-frequency brightness on or off for the CLEAN channel.
  10. CLEAN LEVEL: Adjusts the overall output volume level for the CLEAN channel.
  11. CH SEL: Switches between the CLEAN and DRIVE channels.
  12. DRIVE LEVEL: Adjusts the overall output volume level for the DRIVE channel.
  13. DRIVE BASS: Adjusts the low-frequency response for the DRIVE channel.
  14. DRIVE MIDDLE: Adjusts the middle-frequency response for the DRIVE channel.
  15. DRIVE TREBLE: Adjusts the high-frequency response for the DRIVE channel.
  16. DRIVE GAIN: Adjust the overdrive gain for the DRIVE channel.
  17. INPUT: Two 1/4″ jacks for connecting your guitar.
    Rear Panel
    STAGE RIGHT SB20 50-watt Guitar FIG 2
  18. FOOT SWITCH: 1/4″ jack for connecting an optional foot switch (not included), which can be used to toggle the reverb effect on or off.
  19. EFFECTS RETURN: 1/4″ jack for connecting the output of an effects unit.
  20. EFFECTS SEND: 1/4″ jack for connecting the input of an effects unit.
  21. LINE OUT: 1/4″ jack that carries the unamplified signal to an external device, such as a recording device, mixer, or another amplifier.
  22. SPEAKER OUTPUTS: Three 1/4″ jacks for connecting either one 8-ohm speaker, two 16-ohm speakers, or a single 16-ohm speaker.
  23. AC INPUT: IEC 60320 C14 panel connector for connecting the included AC power cord.
  24. FUSE HOLDER: Always power off and unplug the amplifier before changing the fuse.


Monoprice is pleased to provide free, live, online technical support to assist you with any questions you may have about installation, setup, troubleshooting, or product recommendations. If you ever need assistance with your new product, please come online to talk to one of our friendly and knowledgeable Tech Support Associates. Technical support is available through the online chat button on our website or through email by sending a message to Check the website for support times and links.


Model 625913
Type Tube Guitar Amplifier
Number of Channels 2
Output Power 50 Watts


2x 1/4″ Guitar (High and Low), 1x 1/4″ Effects Return, 1x 1/4″ Foot Switch


3x 1/4″ Speaker (1x 8Ω, 2x 16Ω, and 1x 16Ω), 1x 1/4″ Line Out, 1x 1/4″ Effects Send
Preamp Tubes 3x 12AX7 (V1-V3), 1x 12AT7 (V4)
Power Tubes 2x 6L6G (V5-V6)
Effects Spring Reverb, Overdrive
EQ Bass, Middle, Treble
Fuse Types 120 VAC: F3.15A250V, 240 VAC: F1.6A250V
Cabinet Material MDF
Dimensions 22.4″ x 10.2″ x 10.2″
Weight 36.4 lbs.


Notice for FCC

This device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

Modifying the equipment without Monopile’s authorization may result in the equipment no longer complying with FCC requirements for Class B digital devices. In that event, your right to use the equipment may be limited by FCC regulations, and you may be required to correct any interference to radio or television communications at your own expense.

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

  • Reorient or relocate the receiving antenna.
  • Increase the separation between the equipment and receiver.
  • Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
  • Consult the dealer or an experienced radio/TV technician for help.

Notice for Industry Canada
This Class B digital apparatus complies with Canadian ICES-003.


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