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Thread: Audio Shield 4.0 + electric guitar input

  1. #1
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    Audio Shield 4.0 + electric guitar input

    Does anyone have experience or recommendations on how to interface an analog electric guitar mono signal to the Teensy 4.0 Audio Shield?
    Audio shield "Mic" input or "Line In" input or Teensy A/D input?
    Impedance matching circuit, etc?

    Thanks

    -Joe

  2. #2
    Senior Member oddson's Avatar
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    A buffer from an op amp would make sense to me before the AD pin or the line in input.

  3. #3
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    Quote Originally Posted by JK2940 View Post
    Does anyone have experience or recommendations on how to interface an analog electric guitar mono signal to the Teensy 4.0 Audio Shield?
    Audio shield "Mic" input or "Line In" input or Teensy A/D input?
    Impedance matching circuit, etc?

    Thanks

    -Joe
    Use the line in (combine the L and R)
    Then use the first stage OpAmp from either:
    https://www.electrosmash.com/pedalshield-uno
    or
    http://wiki.openmusiclabs.com/wiki/StompShield

    I attach the schematics - I have used both of these

  4. #4
    Would you power the OP Amp with 3.3v or 5v?

  5. #5
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    Quote Originally Posted by neroroxxx View Post
    Would you power the OP Amp with 3.3v or 5v?
    I used both with an ATMega1284 with a +5v supply but the MCP6001/2/4 data indicates a power supply range of 1.8V to 6.0V, and the TL97x family operates at voltages as low as 1.35 V.

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