Digital synthesizer
The very earliest digital synthesis experiments were made with computers, as part of academic research into sound generation.
These had a pair of fast D/A and A/D converters,[2][3] 12,000 (12k) bytes of core memory (RAM), backed up by a hard drive of 32k and by tape storage (DecTape).
Other techniques, such as wavetable synthesis and physical modeling, only became possible with the advent of high-speed microprocessor and digital signal processing technology.
[11] The Fairlight CMI was the one of the earlier sampling synthesizers,[14] while the Synclavier originally used FM synthesis technology licensed from Yamaha,[15] before adding the world's first 16-bit, real-time hard drive streaming sampler later in 1982.
These use computing power to simulate traditional analog waveforms and circuitry such as envelopes and filters, with the most popular examples of this type of instrument including the Nord Lead and Access Virus.
Digital synthesizers can now be completely emulated in software ("softsynth"), and run on conventional PC hardware.
Such soft implementations require careful programming and a fast CPU to get the same latency response as their dedicated equivalents.
To reduce latency, some professional sound card manufacturers have developed specialized Digital Signal Processing ([DSP]) hardware.
Dedicated digital synthesizers have the advantage of a performance-friendly user interface (physical controls like buttons for selecting features and enabling functionality, and knobs for setting variable parameters).
[18] Yamaha's engineers began adapting Chowning's algorithm for use in a commercial digital synthesizer, adding improvements such as the "key scaling" method to avoid the introduction of distortion that normally occurred in analog systems during frequency modulation, though it would take several years before Yamaha were to release their FM digital synthesizers.
[19] In the 1970s, Yamaha were granted a number of patents, under the company's former name "Nippon Gakki Seizo Kabushiki Kaisha", evolving Chowning's early work on FM synthesis technology.
[25] The DX-7 was also known for its "key scaling" method to avoid distortion and for its recognizably bright tonality that was partly due to its high sampling rate of 57 kHz.
As the cost of processing power and memory fell, new types of synthesizers emerged, offering a variety of novel sound synthesis options.
