Pro Co CB1
Passive Direct Box

OUR PART #  CB1


Pro Co's CB-1 passive direct box is for connecting unbalanced musical instruments and line-level sources to low-Z balanced microphone inputs for PA or recording. Not recommended for speaker-level use. 1/4" (6.35mm) input (with parallel 1/4" output). Switch for ground lift. Male XLR-type balanced mic-level output. Uses Pro Co CBT-1 transformer (20k/150 ohm).

Pro Co CB1 Features:

  • High input impedance minimizes loading for maximum sound
  • Floating transformer-balanced XLR output for maximum isolation
  • GND/LIFT switch eliminates hum and buzz
  • Handles line-level inputs to +20 dBv at 20 Hz
  • Rugged "Uni-box" construction for super-strength and shielding
  • Recessed switches and connectors resist damage
  • Passive design requires no batteries or phantom power

    Pro Co CB1 Specifications:

    • Frequency Response: 20 Hz-20 kHz, +/-1.0 dB @ -15 dBv output
    • Total Harmonic Distortion
      • less than .1% 20 Hz-20 kHz @ -30 dBv output
      • less than .5% 30 Hz-20 kHz @ -15 dBv output
      • less than 1.0% 20 Hz-20 kHz @ -15 dBv output
    • Phase Response: less than -25 degrees @ 20 kHz (ref.1.0 kHz)
    • Rise Time: less than 6.0 microseconds (2.0 kHz square wave, 10%-90%)
    • Input Impedance
      • greater than 185 kohm @ 1.0 kHz
      • greater than 140 kohm @ 10 kHz
    • Output Impedance
      • less than 130 ohm @ 1.0 kHz
      • less than 155 ohm @ 10 kHz
    • Voltage Stepdown: less than 23 dB @ 1.0 kHz
    • Maximum Input Level for 1% THD
      • +20 dBv @ 20 Hz
      • +26 dBv @ 30 Hz
      • +32 dBv @ 50 Hz
    • Dimensions (LxWxH): 4.875" x 4.375" x1.75" (123.8 x 111.1 x 44.4 mm)
    • Weight: 1.0 lb. (0.45 kg)
    • Shipping Weight: 2.0 lbs. (0.91 kg)

    Click to download

    Pro Co CB1
    Passive Direct Box

    OUR PART #  CB1

    Product Information:

    Pro Co's CB-1 passive direct box is for connecting unbalanced musical instruments and line-level sources to low-Z balanced microphone inputs for PA or recording. Not recommended for speaker-level use. 1/4" (6.35mm) input (with parallel 1/4" output). Switch for ground lift. Male XLR-type balanced mic-level output. Uses Pro Co CBT-1 transformer (20k/150 ohm).

    Pro Co CB1 Features:

    • High input impedance minimizes loading for maximum sound
    • Floating transformer-balanced XLR output for maximum isolation
    • GND/LIFT switch eliminates hum and buzz
    • Handles line-level inputs to +20 dBv at 20 Hz
    • Rugged "Uni-box" construction for super-strength and shielding
    • Recessed switches and connectors resist damage
    • Passive design requires no batteries or phantom power

      Pro Co CB1 Specifications:

      • Frequency Response: 20 Hz-20 kHz, +/-1.0 dB @ -15 dBv output
      • Total Harmonic Distortion
        • less than .1% 20 Hz-20 kHz @ -30 dBv output
        • less than .5% 30 Hz-20 kHz @ -15 dBv output
        • less than 1.0% 20 Hz-20 kHz @ -15 dBv output
      • Phase Response: less than -25 degrees @ 20 kHz (ref.1.0 kHz)
      • Rise Time: less than 6.0 microseconds (2.0 kHz square wave, 10%-90%)
      • Input Impedance
        • greater than 185 kohm @ 1.0 kHz
        • greater than 140 kohm @ 10 kHz
      • Output Impedance
        • less than 130 ohm @ 1.0 kHz
        • less than 155 ohm @ 10 kHz
      • Voltage Stepdown: less than 23 dB @ 1.0 kHz
      • Maximum Input Level for 1% THD
        • +20 dBv @ 20 Hz
        • +26 dBv @ 30 Hz
        • +32 dBv @ 50 Hz
      • Dimensions (LxWxH): 4.875" x 4.375" x1.75" (123.8 x 111.1 x 44.4 mm)
      • Weight: 1.0 lb. (0.45 kg)
      • Shipping Weight: 2.0 lbs. (0.91 kg)

      Click to download

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