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Bumper FAQ


Can the Bumper be used on acoustic guitar?

Yes. It is perfectly well suited for those that need alternate tuning on stage or a backup in case of a broken string.

Can the tuner out be used for an amp?

Yes, however this output is not transformer isolated and always on. Therefore, it may cause hum & buzz problems in certain situations. Always connect all of the amps and pedals into the same power bar as this can often help reduce noise.

Will the Drag™ control have any effect on active instruments?

No, not really. You may be able to dull the output slightly at the lowest setting, but for the most part, once a signal has been buffered, the load on the pickup has already been determined.

Will the Drag™ control have any effect on pedals?

It depends. If you are using True-Bypass pedals, when the pedal is out of the circuit, the Drag™ control will affect the pickup. Fuzz and wah pedals are also affected by the load. Try it out!

Can my effects pedals be placed either before or after the Bumper?

Yes. You can have pedals dedicated to one instrument if connected before or have all four instruments be connected through all your pedals if they are connected at the output.

Can I use the Bumper with a power brick?

Yes. For best performance and low noise, always try to use a power brick with 9VDC isolated outputs.

Can you explain Drag™ control?

When you connect your electric guitar or bass to a buffer or amplifier, the input impedance affects the tone. The higher the input impedance, the glassier or brighter the tone. Drag lets you adjust the tone to suit your playing style. Keep in mind that Drag is designed to work on passive instruments like a Gibson Les Paul® or Fender® Jazz bass.

Can I use the Bumper for my mandolin, fiddle, banjo and dobro to feed a PA?

Yes. Simply connect your instruments, use the Trim controls to match the levels and then connect the output to a Radial ProDI™ so that you can feed the PA. If you have the luxury of having four independent channels available, the Radial Four-Play™ will give you even greater flexibility.