Guide to Synthesizers

A synthesizer is an electronic musical instrument that produces electronically generated sound.  It is used to alter or manipulate already existing sounds to voices or other musical instruments and musical arrangements.  It creates sounds by direct manipulation of electrical voltages, by the use of computers and manipulation of discrete values, or a combination of both. It uses subtractive, additive, physical modeling synthesis, FM, and phase distortion techniques to alter sound. It typically comes with a keyboard that provides the human interface for controlling. The keys can be in the form of piano keys, knobs, fingerboards or switchboards, and ribbons. Depending on the model, a synthesizer can have features such as delay, echo, reverb, phaser, distortion, volume, filters, multiple layers, and MIDI setup. 

• An analog synthesizer uses analog circuits and analog computer techniques to produce sound electronically.
• It commonly uses an operational amplifier, an integrated circuit, transistors of microchips, low-pass filters, and high-pass filters.
• It also has a potentiometer, which is a variable resistor that can adjust the trait of the sound produced.
• The early analog synthesizers were derived from the technology of electronic analog computers and lab test equipment. The first ones were generally modular synthesizers with a number of independent electronic modules connected together by patch cables.
• An analog synthesizer is made up of voltage-controlled oscillators, voltage-controlled filters, voltage-controlled amplifiers, envelope generators low-frequency oscillators, ring modulators, reverb units, sequencers, and sound mixers.
• It can take input sound signals and process them for sound-generating and sound-processing use.

• A digital synthesizer is a modern unit.
• It uses DSP (digital signal processing) to make musical sounds.
• It generates a digital sample corresponding to a sound pressure at a given rate of frequency, usually 44,100 samples per second.
• Each digital oscillator is represented by a counter.
• It has its own hardware similar to a keyboard organ.
• It is used as a keyboard, a sampler, a multi-effects device, and a recorder.

• A software-based synthesizer is a digital synthesizer that uses PC hardware instead of a digital keyboard.
• It runs in high-speed computers with large hard drives.
• It uses DSP algorithms or electronic sound ghenerators to create fairly accurate simulations of acoustic sources.

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