A digital synthesizer is a synthesizer that uses digital signal processing (DSP) techniques to make musical sounds. This in contrast to older analog synthesizers, which produce music using analog electronics, and samplers, which play back digital recordings of acoustic, electric, or electronic instruments. Some digital synthesizers emulate analog synthesizers; others include sampling capability in addition to digital synthesis.
Analog vs. digital
The main difference is that a digital synthesizer uses digital processors and analog synthesizers use analog circuitry. A digital synthesizer is in essence a computer with (often) a piano-keyboard and an LCD as an interface. An analog synthesizer is made up of sound-generating circuitry and modulators. Because computer technology is rapidly advancing, it is often possible to offer more features in a digital synthesizer than in an analog synthesizer at a given price. However, both technologies have their own merit. Some forms of synthesis, such as, for instance, sampling and additive synthesis are not feasible in analog synthesizers, while on the other hand, many musicians prefer the character of analog synthesizers over their digital equivalent.
Bands using digital synths
The new wave era of the 1980s first brought the digital synthesizer to the public ear. Bands like Talking Heads and Duran Duran used the digitally made sounds on some of their most popular albums. Other more pop-inspired bands like Hall & Oates began incorporating the digital synthesizer into their sound in the 1980s. Through breakthroughs in technology in the 1990s many modern synthesizers use DSP.
Working in more or less the same way, every digital synthesizer appears similar to a computer. At a steady sample rate, digital synthesis produces a stream of numbers. Sound from speakers is then produced by a conversion to analog form. Through signal generation, voice and instrument-level processing, a signal flow is created and controlled either by MIDI capabilities or voice and instrument-level controls.