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Radial SB-4 Compact Active DI For Piezo Pickups Low-Cut Filter 48V Phantom
  • Radial SB-4 Compact Active DI For Piezo Pickups Low-Cut Filter 48V Phantom
  • Radial SB-4 Compact Active DI For Piezo Pickups Low-Cut Filter 48V Phantom
  • Radial SB-4 Compact Active DI For Piezo Pickups Low-Cut Filter 48V Phantom
  • Radial SB-4 Compact Active DI For Piezo Pickups Low-Cut Filter 48V Phantom
  • Radial SB-4 Compact Active DI For Piezo Pickups Low-Cut Filter 48V Phantom
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Radial SB-4 Compact Active DI For Piezo Pickups Low-Cut Filter 48V Phantom

Manufacturer: Radial Engineering

Item #: RAD-SB-4   •   MFG #: R800 0140


List Price:$90.00
Our Price:$79.99

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Availability: Usually ships in 3-10 business days
This item is currently out of stock and will ship the minute we receive it – typically 3-10 business days. Need it sooner? Expedited delivery options may be available. Email [email protected] or call customer service at 800-522-2025 and we’ll make it happen.



    The Radial StageBug SB-4 is a compact active direct box that has been optimized for use with piezo transducers. This enables violin, dobro, mandolin, cello, upright bass and other instruments that are best amplified using a piezo to be connected without compromising the tone or frequency response.

    The design begins with a 1/4" input for the instrument pickup. Unlike typical direct boxes that have a 1meg-ohm input impedance, the SB-4 features a very high 10meg-ohm impedance that smoothes out troublesome peaks that give piezos a bad name. The higher impedance also broadens the frequency response for a more natural and pleasing sound. The active circuit performs the high-to-low impedance conversion and balances the signal to enable long runs upwards to 100 meters without loss, delivering spectacular linearity and low distortion throughout the audio range.

    To help eliminate feedback on stage, the SB-4 is equipped with a high-pass filter and 180Ý polarity reverse switch. The high pass filter eliminates excessive bottom end which in turn reduces resonance that can cause the top of the instrument to vibrate. The 180Ý polarity reverse helps reduce acoustic hot spots on stage by changing the phase relationship between the PA system and room acoustics which can combine at certain frequencies to create peaks. Reversing the polarity eliminates the acoustic peak without resorting to severe equalization which only serves to compromise the natural tone of the instrument. Connections include an AUX out for a stage amplifier plus a standard XLR output to feed the PA. Power is derived from the console's 48V phantom, thus eliminating the need for batteries or external supply. One simply connects, turns on the phantom power and plays!

    These features combined with the compact size make the StageBug SB-4 the perfect companion for orchestral artists, blue grass players and pop string quartets that need to turn it up when in concert.

    • Features

      • Active DI optimized for piezo transducers
      • Smoothes out peaks, eliminates squawk
      • High pass filter eliminates resonance
      • Ultra compact to fit in your guitar case
    • Specifications

      • Audio circuit type: Piezo optimized active buffer
      • Frequency response: 20Hz to 20kHz
      • Total harmonic distortion: <0.006%
      • Dynamic range: 100dB
      • Input impedance: 5Meg Ohms
      • Maximum input: +4dBu
      • Gain: +2dB
      • Output impedance: 330R Ohms
      • Equivalent input noise: -101dBu
      • Noise floor: -97dBu
      • Intermodulation distortion: <0.01%
      • Phase deviation: 10° @ 50Hz
      • Switches: High Pass Filter, Phase, Ground Lift
      • Low-cut filter: 150 Hz
      • Filter slope: 6dB/octave
      • Instrument input: 1/4" buffered with piezo optimized load
      • Auxilary output: 1/4" buffered to drive guitar effects, amplifier or tuner
      • Balanced output: Pin-1 ground, pin-2 (+), pin-3 (-)
      • Polarity reverse: 180°
      • Ground lift: Soft lift with 100 Ohms to ground
      • Construction: 16 gauge steel chassis & outer shell
      • Finish: Durable powder coat
      • Size: (L x W x D) 4.5" x 1,85" x 1.35" (114mm x 47mm x 34mm)
      • Weight: 0.55 lbs (250 grams)
      • Shipping size: (L x W x D): 8" x 5" x 3" (203mm x 127mm x 76mm)
      • Shipping weight: 0.8 lbs (365 grams)
      • Power requirement: 48V phantom power, 5mA
      • Conditions: For use in dry locations only between 5°C and 40°C
      • Warranty: Radial 3-year, transferable

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