4ms Listen IO

The Listen IO is a simple module which gets signals in and out of a Eurorack system by converting to and from normal modular levels. The top section converts any external signal to modular levels by providing up to 30x gain (+30dB), allowing you to use table-top synthesizers, keyboards, phones/tablets, computers, toys, microphones, etc. in your patches. The bottom section does the opposite: modular signals are converted to normal line level signals. The bottom two jacks can be used as line outs or as headphone jacks, so you and a friend can listen in stereo at the same time.

Each section has two inputs and outputs for use with a stereo signal or two mono signals. An LED bar graph for each output shows the signal level and clipping.

Connect your Listen IO to other Listen modules or the WAV Recorder using the Audio jumper cable

Basic Features:

• Line to modular conversion, and modular to line/headphone conversion
• Works with guitars, table-top synths, effect pedals, keyboards, groove boxes, and many microphones
• Dual mono or stereo conversion
• LEDs show signal level and clipping
• Gain knob allows for wide range of boost or cut
• Headers in back for connecting to Listen Up or DIY adaptor module (1/4", banana, etc.)
• Two headphone outputs and stereo inputs for use as a compact headphones module
• Electrical and Mechanical Specifications:
  • Module size:
    • 6 HP Eurorack format module
    • 0.95" (24mm) maximum depth with power cable
  • Power consumption:
    • Maximum values: All output jacks shorted to ground, 22Vpp signal on all input jacks, knobs at 100%
    • +12V: 62mA
    • -12V: 55mA
  • Line to Mod section (top):
    • Output: 1k impedance
    • Input: 100k impedance
    • Frequency Response: +/-0.1dB max deviation, 20Hz 20kHz
    • Maximum output level: 22V peak-to-peak
    • Maximum gain: +30dB
  • Mod to Line section (bottom):
    • Output: 68 impedance
    • Input: 100k impedance
    • Frequency Response: +/-0.1dB max deviation, 20Hz 20kHz
    • Maximum output level: 22V peak-to-peak
    • Maximum gain: 0dB (unity)
    • Channel cross-talk:
      • Test conditions: Test signal input into left Mod In jack. Sine wave at frequencies from 20Hz to 20kHz tested. Result given as a ratio of the appearance of test frequency measured on right Line Out jack to left Line Out jack. Test repeated with left and right jacks swapped. Worst-case results for any channel and frequency reported.
      • 20Hz 20kHz: <-110dB
  Included with the Listen IO:
  • 10-to-16 pin power cable
  • 2 M3 Knurlie screws