This document is intended for experienced A-100 users who want to modify the timing range of some modules (e.g. envelope generators, LFOs, slew limiters). The pictures show the position(s) of the capacitor(s) which is(are) responsible for the timing of the module in question. To lengten the time or period the capacitor value has to be increased and vice versa. The capacitor value is proportional to the time or period (e.g. doubling the capacitor value even doubles the time or period, when the capacitor value is increased tenfold even the time or period increases tenfold). If an electrolytic capacitor is used one has to pay attention to the polarity (minus and/or plus sign).
All modules that can be modified in that way will be added little by little to this page. Please send a message to hardware@doepfer.de if you need the capacitor position of a module that is still missing.
A-118 Noise/Random Voltage
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Timing (smoothing) capacitors
for random voltage: C8+C8', C9+C9' Standard value: 4.7uF (electrolytic) Polarity C8: minus = top Polarity C8': minus = bottom Polarity C9: minus = top Polarity C9': minus = bottom Remark: For C8 and C8' same values have to be used
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A-119 External Input / Envelope Follower
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Timing (smoothing) capacitors
for envelope follower: C6 Standard value: 100 nF = 0,1uF (foil/mylar) Polarity: none Remark: If a electrolytic capacitor is used a bipolar version is required. Alternatively two standard electrolytic capacitor with the same value connected together in opposite direction can be used (the resulting capacity is half the value of each capacitor). For example refer to C8/C8' and C9/C9' of A-118. |
A-140 ADSR
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Timing capacitors
(long range): C4 Standard value: 100uF (electrolytic) Polarity: minus = left Timing capacitor (mid range):
C3 Timing capacitor (short range): C2
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A-141 VCADSR
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Timing capacitor: C2 Standard value: 100nF = 0.1uF (foil/mylar) Polarity: none if electrolytic capacitors are used the minus pole has to be connected to GND (i.e. to the pin that is connected to the GND plane of the pc board) |
A-142 VC Decay/Gate
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Timing capacitor: C3 Standard value: 100nF = 0.1uF (foil/mylar) Polarity: none if electrolytic capacitors are used the minus pole has to be connected to GND (i.e. to the pin that is connected to the GND plane of the pc board) |
A-142-4 Quad Decay
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Timing capacitors:
C2, C4, C6, C8 Standard value: 470nF = 0.47uF Polarity: none if electrolytic capacitors are used the minus pole has to be connected to GND (i.e. to the pin that is connected to the GND plane of the pc board) |
A-143-1 Quad AD
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Timing capacitor: C1 Standard value: 2.2uF (electrolytic), corresponds to about 5 ms shortest Attack/Decay time Polarity: plus = left |
A-143-2 Quad ADSR
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Timing capacitor
(long range): C1 Standard value: 100uF (electrolytic) Polarity: plus = left Timing capacitor (mid range): C9 Timing capacitor (short range): C10 |
A-143-3 Quad LFO
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Timing capacitors
(long range): C3+C4 Standard value: 2.2uF (electrolytic) Polarity (upper): minus = left Polarity (lower): plus = left Remark: If C3 and C4 are replaced same values have to be used (e.g. 2 x 1uF) Timing capacitor (mid range): C2 Timing capacitor (short range): C1 |
A-145 Standard LFO (LFO I)
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Timing capacitors
(long range): C3+C4 Standard value: 2.2uF (electrolytic) Polarity C3: minus = top Polarity C4: minus = bottom Remark: If C3 and C4 are replaced same values have to be used (e.g. 2 x 10uF) Timing capacitor (mid range): C2 Timing capacitor (short range): C1
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A-146 Variable Waveform LFO (LFO II)
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Timing capacitors
(long range): C3+C4 Standard value: 2.2uF (electrolytic) Polarity C3: minus = right Polarity C4: minus = left Remark: If C3 and C4 are replaced same values have to be used (e.g. 2 x 10uF) Timing capacitor (mid range): C2 Timing capacitor (short range): C1
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A-147 VCLFO
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Timing capacitor: C2 |
A-162 Dual Trigger Delay
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Timing capacitors: |