Speaker Calibration

Speaker calibration sets the attenuation values used when Etho loads playlist stimuli. The goal is that playlist intensity values correspond to the sound unit convention used by the rig.

Hardware Setup

  1. Place the microphone at the animal position.

  2. Record the distance and geometry relative to the speaker.

  3. Connect the microphone amplifier output to a DAQ analog input.

  4. Use the same playback output path and amplifier settings used during experiments.

  5. Record the microphone calibration file, date, and gain settings.

Run Calibration Stimuli

Use a calibration playlist that covers the frequency and intensity range needed for experiments. During the run, save:

  • raw microphone recording

  • protocol file

  • playlist file

  • current ethoconfig.yml

  • microphone calibration metadata

  • rig name and date

Analyze And Update

Analyze the recorded response to calculate attenuation factors for the frequencies used in playlists. Store the resulting mapping in ~/ethoconfig/ethoconfig.yml under ATTENUATION.

Example:

ATTENUATION:
  -1: 1
  100: 0.82
  150: 0.77
  200: 0.74

After updating attenuation, run a validation playlist and confirm the measured output matches the target within the tolerance used by the rig.

Suggested File Layout

playback/
  calibration/
    mic_calibration/
      mic_calibration_YYYYMMDD.yml
    YYYYMMDD/
      rig_name_before.csv
      ethoconfig_rig_name_before.yml
      rig_name_after.csv
      ethoconfig_rig_name_after.yml
      figures/

Keep enough metadata with the calibration data that another operator can repeat or audit the calibration later.