Build Guide - Calibration

ADSR ENVELOPE

Test Point   Procedure
TP-C6

  1. Monitor TP-C6 with an oscilloscope
  2. Set [ATTACK], [DECAY] and [RELASE] fully counter-clockwise and [SUSTAIN] fully clockwise
  3. Press and hold 'MIDDLE C' for 2 seconds and then release and wait for 2 seconds
  4. Confirm that the signal quickly rises from 0V to over +8V and returns to 0V when the key is release
  5. Set [SUSTAIN] to '5'
  6. Press and hold 'MIDDLE C' for 2 seconds and then release and wait for 2 seconds
  7. Confirm that the signal quickly rises from 0V to over +8V and then quickly drops to about +4V where it should remain until the key is released
  8. Confirm that adjusting [ATTACK], [DECAY] & [RELEASE] varies the rise and fall times of their respective slopes
  9. and that adjusting [SUSTAIN] varies the level at which the 'held on' level rests
TP-B10

 
  1. Monitor TP-B10 with an oscilloscope
  2. Set [ATTACK], [DECAY] & [RELEASE] to '2'
  3. Set [SUSTAIN] to '5'
  4. Press and hold 'MIDDLE C' for 2 seconds and then release and wait for 2 seconds
  5. Confirm that the observed signal is inverted and swings from 0V to approximately -4V

AR ENVELOPE

Test Point   Procedure
TP-C5

ATTACK

RELEASE
  1. Monitor TP-C5 with an oscilloscope
  2. Set [ATTACK] and [RELEASE] fully counter-clockwise
  3. Press and hold 'MIDDLE C' for 2 seconds and then release
  4. Confirm that the signals rises quickly from 0V to +10V and returns quickly to 0V when the key is released
  5. Confirm that adjusting [ATTACK] & [RELEASE] varies the rise and fall times of their respective slopes

LFO

Test Point   Procedure
TP-B7

FREQUENCY
  1. Monitor TP-B7 with an oscilloscope
  2. Confirm that adjusting [FREQUENCY] varies the rate of the LFO TRIANGLE waveform from a period of around 9 seconds per cycle to over 20Hz
  3. Confirm that the waveform swings approximately from -4V to +4V
TP-B8

FREQUENCY
  1. Monitor TP-B8 with an oscilloscope
  2. Confirm that signal is a squarewave with an approximate 50% duty-cycle
  3. Confirm that the signals swings from 0V to over +12V

NOISE

Test Point   Procedure
TP-A9
  1. Monitor TP-A9 with an oscilloscope and confirm that you see WHITE Noise with an amplitude of around 10Vp-p centered around 0V
TP-A10
  1. Monitor TP-A10 with an oscilloscope and confirm that you see PINK Noise with an amplitude of around 7Vp-p centered around 0V

 
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