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Bumper™ Instrument Selector

Part no. R800 7094 00
  • Connect up to four instruments to your stage amp
  • Sequential footswitch selector with LED's
  • Choice of Drag™ control or Trim on each input
  • Radial's Class-A input buffer for absolute best sound

The Bumper™ is a unity gain instrument selector that lets you connect up to four instruments and progressively advance through each input using a sequential footswitch. The sequence is determined by the input conections, whereby if only two instruments are plugged in, the footswitch will only toggle between the ones that are connected.

Each input features Radial's award-winning Class-A buffer for absolute fidelity while enabling longer cable runs without signal degradation. This is augmented with Drag™ control load correction that lets you adjust the load on each instrument for optimal signal transfer, natural tone and feel. Drag works equally well on single coil or humbucking pickups – on both electric guitar and bass. A selector switch for each input changes the Drag™ control to a Trim to balance louder sources such as an active bass or acoustic guitar with passive counterparts. This lets you quickly switch instruments without having to readjust levels on the stage amp. In addition to the ¼" stage amp output, the Bumper is equipped with a separately buffered tuner output. This is always on to allow on-the-fly tuning while eliminating any clocking noise or loading caused by the tuner.

Compact and made from 14-gauge steel, the Bumper is well equipped to protect against the harsh environment of professional touring while ensuring the instrument signal will be shielded against stray magnetic fields. Powered by a standard 9V supply, it can easily be integrated into a pedalboard using an off-the-shelf Boss®-style supply or multi-output power brick.

The Tonebone Bumper is the perfect interface for multi-instrumentalists, studio session players or artists that employ several guitars on stage.


Effects Loop Controller


Acoustic Instrument Preamp


2-Channel Bass


Select between 3 electric guitars

With only three instruments connected, the Bumper will only rotate through these, ignoring input-4. Set the Drag control for each instrument to replicate the tone and feel as if connected directly to your amp.

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Select between four basses

Combine active and passive basses using the Drag control on your Fenders® and the Trim to balance your active 5 and 6 string basses so that they all play at the same level. Add a tuner using the dedicated output.

Select between four acoustics

Instantly switch between your dreadnaught, 12 string, mandolin and dobro. Set the Drag when using a magnetic pickup and then match the rest of your instruments using the Trim controls.