Radial Engineering STAGEBUG-SB2
StageBug SB-2 Compact Passive DI for Instruments


If you're a player on the move, the Radial Engineering StageBug™ SB-2 Passive is a high-performance direct box for you. Made to fit inside of a guitar case, the SB-2 is ultra compact, yet feature-packed, so it can ensure great performance on any stage.

Its compact design starts with a ¼" input and thru-put to feed the on-stage amp. This connects to its custom made Eclipse ET-DB3 transformer which performs impedance matching and balancing of the signal. When using extra-high output instruments, a -15dB pad can be inserted into the signal path. This allows the SB-2 to be used with active basses and digital pianos that often tend to overload the input side of the interface. The innovative stereo-to-mono merge function offers a convenient way to connect stereo keyboards and computers with no need to have to reset the source for mono operation, thus saving time and input channels on the PA. The SB-2 output features an XLRM connector wired to the AES standard with pin-2 hot.

Once connected, it delivers a warm, smooth sound reminiscent of vintage gear. The Eclipse ET-DB3 transformer is almost magical in its ability to handle extreme signal levels with a natural compression that's pleasing to the ears. The transformer also helps eliminate ground loop hum and buzz by isolating the input from the output. This is also augmented with a ground lift switch that lifts pin-1 on the XLR for quiet, professional results.

All these features combine to make the StageBug SB-2 a great choice for electric bass, acoustic guitar, and keyboards where small size and big performance count.

Radial Engineering StageBug SB-2 Features:

  • Passive DI for bass, acoustic and keyboard
  • Ultra compact to fit in your guitar case
  • Plug & play, easy to use feature set
  • Transformer isolation eliminates noise

Radial Engineering StageBug SB-2 Specifications:


  • Audio circuit type: Passive, transformer based
  • Number of channels: Single channel (mono)
  • Frequency response: 20Hz ~ 20KHz (± 0.5dB)
  • Dynamic range: 115dB
  • Maximum input: +20dB
  • Total harmonic distortion: 0.005% @ 1kHz
  • Phase deviation: 3° @ 100Hz; 8° @ 50Hz
  • Input impedance: 140 kOhms, unbalanced
  • Output impedance: 1 kOhms, balanced
  • Transformer: Eclipse ET-DB3, 12:1 ratio
  • Shield: Copper foil
  • Input pad: -10dB 
  • Auto merge: Sums left & right sources to mono
  • Ground lift: Disconnects pin-1 at XLR output
  • XLR configuration: AES standard (pin-2 hot)
  • Connectors: 1/4" in & thru, XLR-M out
  • Block Diagram:

  • Frequency Response:


  • Construction: 14 gauge steel chassis & outer shell
  • Finish: Durable powder coat
  • Dimensions (LxWxD):
    • Product: 4.5" x 1.85" x 1.35" (114mm x 47mm x 34mm)
    • Shipping: 8" x 5" x 3" (203mm x 127mm x 76mm)
  • Weight:
    • Product: 0.55 lbs (250 grams)
      Shipping: 0.8 lbs (365 grams)
  • Power: Passive, no power required
  • Environment Operating Conditions: for use in dry locations only between 41° F and 104° F (5° C and 40° C)
  • Warranty: Radial 3-year, transferable

All specifications & information subject to change without notice.

WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov.

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