Yamaha PSRS700 Arranger Workstation Keyboard » Synthesis Methods

All You Need To Know About Synthesizers

Thu, 24 Dec 2009 20:37:56 +0000

Synthesizers are sound modifying and reproducing units. They can be either installed on a computer system or be physical like the classical synthesizers produced by Yamaha. Synthesizers help in modifying music to make it better, reproduce voice or analyze and come up with a completely different thing all together from the original.

There are 2 basic kinds of synthesizers: analog and digital. Many synthesis methods however exist which apply to both the above types of synthesizers. All these methods tend to be mathematically related for example, frequency modulation and phase modulation.
Some of these types are Subtractive synthesis, Additive synthesis, granular synthesis and wavetable synthesis.

The first true electronic musical synthesizer was invented by Relish Gray in 1876. While working at his telephone invention, Gray discovered that he could control sound from a self vibrating electromagnetic circuit and in doing so invented a basic single note oscillator. After this, synthesizers were controlled by early electronic analog computers and old electronic musical instruments. In 1950, RCA produced experimental devices to synthesize both voice and music. The giant Mark II Music Synthesizer could however synthesize only when it was programmed for a musical or voice performance.

Most modern synthesizers are however digital in nature. They are controlled by what is known as a digital signal processor or DSP. Some digital synthesizers are software that can modify sound using our daily computer machines.

The earliest digital synthesis was performed by software installed on huge main frame computers. Today, various complicated software exist that use the DSP technique to give you a taste of the real thing. They can even reproduce the classical analog synthesizers.

So how are synthesizers used? Well, in many ways. As modern technology evolved, uses have been found for synthesizers. Today synthesis is used to produce high quality music, movies and even voice packages. Groups as early as the Beatles used synthesis techniques in their work. They were followed by the hugely popular Pink Floyd.

Synthesizers are today used also to produce human simulated speech for call centers and multinational companies. People with visual impairments use this technology through a text to speech software that gives them access to modern computers making them independent. Dictation software like the Dragon naturally speaking also uses speech synthesis.

So how do synthesizers reproduce human voice? Voice synthesis is a fascinating topic. A recorded sample of a human voice can be modified so that it is completely different from the original. The sample can be used to generate codes that can be fed into a computer system to give it a voice. In movies, voice modification is done through digital synthesizers to give new and astounding speech to sci fi characters.

Synthesizers are a part of us today. They help us in every aspect of our lives. Starting from your washing machine to the latest robotics every one uses some form of synthesis with the help of digital synthesizing software. Musical instruments can be reproduced on your personal computer allowing you to become the next great artist without even learning to play. They can simulate and reproduce human voice allowing for great software like screen readers, speech recognition and other new and amazing packages.

Features of Synthesizers

Thu, 24 Dec 2009 17:22:24 +0000

A synthesizer is a kind of electronic musical instrument, or electronic device capable of producing or manipulating audio tones, such as musical notes, through audio signal processing. The term originates from the Greek word Syntithetai. One of the main features of synthesizers is that they work by manipulating electrical signals, which appear as sound when they are used to drive audio amplifiers. Music synthesizers sometimes include a keyboard, which remind us of certain traditional musical instruments.
There are three major kinds of synthesizers depending on the different features of synthesizers
Analog
Digital
Software
In addition there are synthesizers that rely upon combinations of those three kinds, known as hybrid synthesizers having a different set of features of synthesizers. Analog synthesizers were the first to be created and developed. After that, came the digital synthesizers. Both analog and digital synthesizers use the same kinds of synthesis methods. These methods are used especially for frequency modulation and phase modulation. Some of the methods are stated below
Subtractive synthesis
Additive synthesis
Frequency modulation synthesis
Phase distortion synthesis
Sample based synthesis
Sub harmonic synthesis
Granular synthesis
Wavetable synthesis
Early features of synthesizers include using the technology derived from electronic analog computers, laboratory test equipment, and early electronic musical instruments.
Brief features of Analog synthesizers
An analog synthesizer is a synthesizer that uses analog circuits and analog computer techniques to generate sound electronically. A very common point among the features of synthesizers of this kind is circuit component; it is the operational amplifier which is a kind of integrated circuit in most of the analog synthesizers. An analog synthesizer could be used both as a sound generating and sound processing system. A very specialized form of analog synthesizer was the analog vocoder, based on equipment developed for speech synthesis. Synthesizer modules found in early analog synthesizers included:
VCO or voltage controlled oscillators
VCF or voltage controlled filters
VCA or voltage controlled amplifiers
Envelope Generators
LFO or low frequency oscillators
Ring Modulators
Sequencers
Some facts about Digital synthesizers
As technology advanced into the digital domain, the new digital technology started coming up in their new designs. Analog synthesizers were mostly replaced by digital synthesizers and samplers over the early mid 1980s. Gradually the voltage controlled analog synthesizers circuits were replaced by microprocessor controlled digital circuits.
The digital synthesizers have advanced features of synthesizers. They have a completely different and advanced sound clarity, since their internal sounds are stored in memory as arrays of numbers. The first breed of digital synthesizers had a much more slick and clean design where the user could program the instrument using a menu driven operating system. One of the first real time polyphonic digital music synthesizers was the Coupland Digital Music Synthesizer.
Basic modules of synthesizers
Three most important modules shaping the features of synthesizers are
The Oscillators
A simple oscillator can create one or two basic waveforms. They are saw tooth wave and a square wave. These waveforms are very simple and completely artificial.
The Filters
A filter is an electronic circuit, which works by smoothing out the edges of the original waveform. Synthesizers use filters to vary the basic waveforms to some extent.
The Amplifiers
The amplifiers can raise, or lower the height of the waveform, thereby raising or lowering the volume of the sound. To control the volume of a sound in the synthesizer, the signal is passed through an amplifier circuit.
Conclusion
Synthesizers were developed in the early twentieth century. It has advanced remarkably in time and has attained a distinguishable position in the music industry. It has now become an indispensable part of every music concert.

Synthesis Methods Of The Electronic Keyboard

Tue, 22 Dec 2009 14:16:52 +0000

Electronic keyboard synthesizers have come a long way since their inception. Few people know that the first electronic synthesizer was invented in the late 1800s. This model was, of course, only a very rough precursor to the musical synthesizers of today. Modern synthesizers are capable of producing a variety of sounds by generating and combining signals of different frequencies. This process is called synthesis, and it can be divided into five distinct types: wavetable, physical modeling, digital, fingerboard and software (digital).
Wavetable synthesis uses an existing sound to create a digital recording, which is known as a sample. This recording can be replayed at a range of pitches. While other synthesis methods use oscillator circuits to produce repetitive electronic signals, wavetable synthesis uses sample playback. If an artist wants to change the musical tone of a passage, the speed of the playback is quickened or slowed accordingly. For instance, in order to alter the frequency of a sound one octave higher, it is played at double speed. Wavetable synthesis is used in certain digital music synthesizers to implement real-time additive synthesis and direct digital synthesis with minimum hardware.
Physical modeling synthesis uses a set of equations and algorithms to simulate the desired physical source of a sound. In order to generate a specific sound, an initial set of parameters is run through the physical simulation. Physical modeling is based on the concepts of acoustics and synthesis. The development of the Karplus-Strong algorithm and the increase in digital signal processor (DSP) power in the late 1980s allowed for the commercial implementations of modern synthesizer physical modeling.
Digital synthesis involves using a digital oscillator to generate a digital sample that corresponds to a sound pressure at a given sampling frequency. In most basic instances, the digital oscillator is modulated by a counter. For each generated sample, the counter is advanced by an amount determined by the frequency of the oscillator. The values are recorded by the oscillator’s counter, mixed, processed and sent to a digital-to-analog converter. The resulting analog signal is then sent to an analog amplifier, which converts the signal to sound.
Fingerboard synthesis utilizes a ribbon controller, which is a user interface used to control the parameters of analog synthesizers. A ribbon controller is similar to the touchpad of a laptop computer in that it registers and translates the motion and position of the user’s fingers. However, most ribbon controllers only register linear motion. Although it could hypothetically be used to alter and control any sound parameter, a ribbon controller is most commonly associated with pitch control or pitch bending.
Digital synthesis is possible on most modern, high-speed personal computers through a variety of available software. DSP algorithms are commonplace, and they allow for the creation of fairly accurate simulations of physical acoustic sources or electronic sound generators. Some commercial programs offer quite lavish and complex models of classic synthesizers. Other programs permit the user complete control of all aspects of digital music synthesis, although such programs can be expensive and difficult to use.