The master's thesis describes the operation of six modules of a modular sound synthesizer. The thesis begins with an introduction to modular sound synthesis, followed by a detailed description and explanation of the operation of each module. The explanation is supported by theory and equations throughout.
For the voltage-controlled oscillator, the approach to achieveing the appropriate ratio between the control voltage and the frequency of the signals is presented. This is followed by a description of the technique for generating various waveform shapes.
The main focus of the ADSR envelope generator, is on the technique for recording states and transitions between them. The voltage control of the duration of states is explained and the longest and shortest state times are computed.
Next, the operation of the sequencer is described. An analysis of the internal clock's operation is presented and various methods of step sequencing and their implementation are discussed. Finally, a section of the circuit responsible for generating analog signals at the sequencer's output is described.
The presentation of the low-frequency oscillator focuses on the implementation of the driving circuit and how it differs from the voltage-controlled oscillator. The technique for generating various waveform shapes at the modules output is also explained.
For the voltage-controlled amplifier circuit, the linear and exponential amplification response based on the control voltage is explained and the dependance for the output current on the control voltage is derived.
For the voltage-controlled filter, the theory of state variable filters is presented and the basic building blocks of such filters are introduced. Then, the operation of the circuit is analyzed and which parts of the circuit corresponding to each basic building block are described.
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