YAMAHA DX7
Overview
Frequency Modulation
DX7 can be seen as a digital modular synthesizer. 6 sine wave oscillators (called Operators) are connected by the routing patterns called Algorithm.
Operators can interact each other by Frequency Modulation (FM). FM works like a kind of Filter/Wavetable sweep. Multiple FM connection produces complex harmonics.
The modulating operator is called Modulator, and the modulated operator is Carrier.
The Carrier's envelope works as VCA, and the Modulator's works as timbre control.
Each operator has its own 4-stage multi-step envelope generator. The envelope is very fast as the early digital synthesizer.
There is 1 LFO that can be used for pitch/amplitude/timbre modulation. There is 1 Pitch Envelope and it's not very fast.
The Spec
DX7 is a 16-polyphonic, mono-timbral synthesizer with velocity and channel aftertouch.
No effects, 1 mono output jack, 12-bit D/A converter.
It's one of the earliest synth with MIDI and good SysEx implementation.
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DX7
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12. 8. 2005