1. Set general instrument defaults.
2. Perform standard WDRC autofit.

1. If HearingThresholdLevel@6.5kHz >= 55 dB, then Equalizer@6.5kHz = -7 dB.
2. If HearingThresholdLevel@8kHz >= 60 dB, then Equalizer@8kHz = -10 dB.

1. Set CrossoverFreq1 = 0.313 Hz.
2. If HearingThresholdLevelAvg(Freq250, Freq500, Freq1000 Hz) ⇐ 30 dB, then CrossoverFreq2 = 0.938 Hz.
3. ElseIf HearingThresholdLevelAvg(Freq250, Freq500, Freq1000 Hz) > 30 dB, then CrossoverFreq2 = 1.063 Hz.
4. If HearingThresholdLevelAvg(Freq2000, Freq4000 Hz) >= 45 dB, then CrossoverFreq3 = 5.313 Hz.

Pre-conditions:

• In Audiogram, frequencies 250, 500 and 750 Hz must exist by either user input or extrapolation/interpolation.

Settings:

1. If HearingThresholdLevelAvg(Freq250, Freq500, Freq750 Hz) ⇐ 45 dB, then NoiseReduction = 'medium (9 dB)'.
2. ElseIf HearingThresholdLevelAvg(Freq250, Freq500, Freq750 Hz) > 45 dB and ⇐ 55 dB, then NoiseReduction = 'low (6 dB)'.
3. ElseIf HearingThresholdLevelAvg(Freq250, Freq500, Freq750 Hz) > 55 dB and ⇐ 60 dB, then NoiseReduction = 'minimum (3 dB)'.
4. ElseIf HearingThresholdLevelAvg(Freq250, Freq500, Freq750 Hz) > 60 dB, then NoiseReduction = 'off (0 dB)'.

1. Feedback Canceller = On.

Pre-conditions:

• In Audiogram, frequency 6 kHz must exist by either user input or interpolation.

Settings:

1. Channel 1:
   • If HearingThresholdLevel@Freq250Hz ⇐ 20 dB, Ch1SoftGain = 4 dB.
   • ElseIf HearingThresholdLevel@Freq250Hz > 20 dB and ⇐ 40 dB, Ch1SoftGain = 10 dB.
   • ElseIf HearingThresholdLevel@Freq250Hz > 40 dB and ⇐ 55 dB, Ch1SoftGain = 14 dB.
   • ElseIf HearingThresholdLevel@Freq250Hz > 55 dB and ⇐ 65 dB, Ch1SoftGain = 21 dB.
   • ElseIf HearingThresholdLevel@Freq250Hz > 65 dB and ⇐ 79 dB, Ch1SoftGain = 26 dB.
   • ElseIf HearingThresholdLevel@Freq250Hz > 79 dB, Ch1SoftGain = 34 dB.
2. Channel 2:
   • If HearingThresholdLevelAvg(Freq500Hz, Freq1000 Hz) ⇐ 29 dB, Ch2SoftGain = 14 dB.
   • ElseIf HearingThresholdLevelAvg(Freq500Hz, Freq1000 Hz) > 29 dB and ⇐ 45 dB, Ch2SoftGain = 18 dB.
   • ElseIf HearingThresholdLevelAvg(Freq500Hz, Freq1000 Hz) > 45 dB and ⇐ 55 dB, Ch2SoftGain = 20 dB.
   • ElseIf HearingThresholdLevelAvg(Freq500Hz, Freq1000 Hz) > 55 dB and ⇐ 65 dB, Ch2SoftGain = 22 dB.
   • ElseIf HearingThresholdLevelAvg(Freq500Hz, Freq1000 Hz) > 65 dB and ⇐ 79 dB, Ch2SoftGain = 30 dB.
   • ElseIf HearingThresholdLevelAvg(Freq500Hz, Freq1000 Hz) > 79 dB, Ch2SoftGain = 36 dB.
3. Channel 3:
   • If HearingThresholdLevel@Freq2000Hz ⇐ 40 dB, Ch3SoftGain = 20 dB.
   • ElseIf HearingThresholdLevel@Freq2000Hz > 40 dB and ⇐ 55 dB, Ch3SoftGain = 26 dB.
   • ElseIf HearingThresholdLevel@Freq2000Hz > 55 dB and ⇐ 65 dB, Ch3SoftGain = 32 dB.
   • ElseIf HearingThresholdLevel@Freq2000Hz > 65 dB and ⇐ 79 dB, Ch3SoftGain = 34 dB.
   • ElseIf HearingThresholdLevel@Freq2000Hz > 79 dB, Ch3SoftGain = 38 dB.
4. Channel 4:
   • If HearingThresholdLevelAvg(Freq4000, Freq6000 Hz) ⇐ 45 dB, Ch4SoftGain = 16 dB.
   • ElseIf HearingThresholdLevelAvg(Freq4000, Freq6000 Hz) > 45 and ⇐ 55 dB, Ch4SoftGain = 22 dB.
   • ElseIf HearingThresholdLevelAvg(Freq4000, Freq6000 Hz) > 55 and ⇐ 65 dB, Ch4SoftGain = 26 dB.
   • ElseIf HearingThresholdLevelAvg(Freq4000, Freq6000 Hz) > 65 and ⇐ 79 dB, Ch4SoftGain = 28 dB.
   • ElseIf HearingThresholdLevelAvg(Freq4000, Freq6000 Hz) > 79 dB, Ch4SoftGain = 30 dB.

Pre-conditions:

• In Audiogram, frequency 250 Hz must exist by either user input or extrapolation.

Settings:

1. If HearingThresholdLevelAvg(Freq250, Freq500 Hz) ⇐ 40 dB, then Expansion(all channels) = 40 dB.
2. ElseIf HearingThresholdLevelAvg(Freq250, Freq500 Hz) > 40 dB and ⇐ 50 dB, then Expansion(all channels) = 34 dB.
3. ElseIf HearingThresholdLevelAvg(Freq250, Freq500 Hz) > 50 dB and ⇐ 60 dB, then Expansion(all channels) = 26 dB.
4. ElseIf HearingThresholdLevelAvg(Freq250, Freq500 Hz) > 60 dB, then Expansion(all channels) = 20 dB.

Pre-conditions:

• In Audiogram, frequency 250 Hz must exist by either user input or extrapolation.

Settings:

1. If HearingThresholdLevelAvg(Freq250, Freq500 Hz) ⇐ 50 dB, then ExpansionRatio(all channels) = 1:3.
2. ElseIf HearingThresholdLevelAvg(Freq250, Freq500 Hz) > 50 dB, then ExpansionRatio(all channels) = 1:2.

Pre-conditions:

• In Audiogram, frequency 250 Hz must exist by either user input or extrapolation.

Settings for Gain Control:

1. If HearingThresholdLevelAvg(Freq250, Freq500, Freq1000 Hz) ⇐ 30 dB, then GainControl = -24dB.
2. ElseIf HearingThresholdLevelAvg(Freq250, Freq500, Freq1000 Hz) > 30 dB and ⇐ 55 dB, then GainControl = -20dB.
3. ElseIf HearingThresholdLevelAvg(Freq250, Freq500, Freq1000 Hz) > 55 dB and ⇐ 79 dB, then GainControl = -18dB.
4. ElseIf HearingThresholdLevelAvg(Freq250, Freq500, Freq1000 Hz) > 79 dB, then GainControl = -0dB.

Settings for User Volume Control:

1. If HearingThresholdLevelAvg(Freq1000, Freq2000 Hz) ⇐ 40 dB, then UserVolControl = 50%.
2. ElseIf HearingThresholdLevelAvg(Freq1000, Freq2000 Hz) > 40 dB and ⇐ 80 dB, then UserVolControl = 75%.
3. ElseIf HearingThresholdLevelAvg(Freq1000, Freq2000 Hz) > 80 dB, then UserVolControl = 100%.

Pre-conditions:

• In Audiogram, frequencies 250 and 6000 Hz must exist by either user input or extrapolation.

Settings:

1. Channel 1:
   • If HearingThresholdLevel@Freq250Hz ⇐ 35 dB, then Ch1CompressionRatio = 1.7:1, Ch1LowTK = 40 dB.
   • ElseIf HearingThresholdLevel@Freq250Hz > 35 dB and ⇐ 44 dB, then Ch1CompressionRatio = 1.6:1, Ch1LowTK = 48 dB.
   • ElseIf HearingThresholdLevel@Freq250Hz > 44 dB and ⇐ 55 dB, then Ch1CompressionRatio = 1.5:1, Ch1LowTK = 50 dB.
   • ElseIf HearingThresholdLevel@Freq250Hz > 55 dB and ⇐ 65 dB, then Ch1CompressionRatio = 1.4:1, Ch1LowTK = 52 dB.
   • ElseIf HearingThresholdLevel@Freq250Hz > 65 dB, then Ch1CompressionRatio = 1.3:1, Ch1LowTK = 54 dB.
2. Channel 2:
   • If HearingThresholdLevelAvg(Freq500, Freq750 Hz) ⇐ 35 dB, then Ch2CompressionRatio = 1.7:1, Ch2LowTK = 46 dB.
   • ElseIf HearingThresholdLevelAvg(Freq500, Freq750 Hz) > 35 dB and ⇐ 55 dB, then Ch2CompressionRatio = 1.5:1, Ch2LowTK = 50 dB.
   • ElseIf HearingThresholdLevelAvg(Freq500, Freq750 Hz) > 54 dB and ⇐ 65 dB, then Ch2CompressionRatio = 1.4:1, Ch2LowTK = 55 dB.
   • ElseIf HearingThresholdLevelAvg(Freq500, Freq750 Hz) > 65 dB, then Ch2CompressionRatio = 1.3:1, Ch2LowTK = 58 dB.
3. Channel 3:
   • If HearingThresholdLevelAvg(Freq2000, Freq4000, Freq6000 Hz) < 40 dB, then Ch3CompressionRatio = 1.3:1, Ch3LowTK = 54 dB.
   • ElseIf HearingThresholdLevelAvg(Freq2000, Freq4000, Freq6000 Hz) >= 40 dB, then Ch3CompressionRatio = 1.3:1, Ch3LowTK = 60 dB.
4. Channel 4:
   • If HearingThresholdLevelAvg(Freq6000, Freq8000 Hz) < 40 dB, then Ch4CompressionRatio = 1.4:1, Ch4LowTK = 52 dB.
   • ElseIf HearingThresholdLevelAvg(Freq6000, Freq8000 Hz) >= 40 dB, then Ch4CompressionRatio = 1.3:1, Ch4LowTK = 56 dB.