"The Grapher is the machine's user interface and is what Technos flaunted in all of its ads. It's an arresting device, consisting of a vacuum-fluorescent display for status information and menus and a surface of touch-sensitive (capacitance-driven, I believe) nodules, 2114 of which contain LEDs. Yes, that's correct: over two thousand LEDs. The main array, the matrix, is 64 units across by 32 high. It is used to adjust spectra, envelopes, and waveforms. Above this is a row of 32 nodules which represent loop points; it is also used as a crude alphabetic keyboard when naming patches. Below the matrix is another row of 32 nodules that is used for selecting what elements of the synthesis architecture to enable or to select the current object to work with. These have a similar function to the four "layer" buttons on the JD-800.
On either side of the matrix are columns of nodules used to select the data the matrix displays, the operation mode, loading and saving of sounds, and so on. "
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