Fretboard to synthesizer interface apparatus

Claim 2

Fretboard to synthesizer interface apparatus including a fretboard having a plurality of frets and a plurality of strings stretched thereover comprising: means for causing a current to flow through each of a succession of said strings; means for detecting a differential voltage across each of a succession of adjacent fret pairs of said guitar, which voltage is indicative of a depression of a said string at the fret position bracketed by said fret pair, and for generating a control signal upon said detection; and means for maintaining a count indicative of the fret pair under examination by said detecting means and for latching said count in response to said control signal.

Claim 3

The apparatus of claim 1 wherein said means for detecting a voltage includes a conductor connecting each of said frets to ground.

Claim 4

Guitar to synthesizer apparatus comprising: means for causing a current to flow through a succession of guitar strings; differential amplifier means; means for conductively connecting a succession of adjacent pairs of frets of said guitar to said differential amplifier means; counter means for maintaining a count indicative of the string subjected to a current by said means for causing current flow and indicative of the fret pair connected to said differential amplifier means; comparator means for comparing the output of said differential amplifier to a reference level and providing a control signal to latch the count of said counter means upon detection of a differential output in excess of said reference level.

Claim 5

Guitar to synthesizer apparatus comprising: means for causing a current to flow through a succession of guitar strings; differential amplifier means; means for conductively connecting a succession of adjacent pairs of frets of said guitar to said differential amplifier means; counter means for maintaining a count indicative of the string subjected to a current by said means for causing current flow and indicative of the fret pair connected to said differential amplifier means; comparator means for comparing the output of said differential amplifier to a reference level and providing a control signal to latch the count of said counter means upon detection of a differential output in excess of said reference level.

Claim 6

The apparatus of claim 2 further including shorting string means connecting each fret to ground.

Claim 7

Apparatus for detecting a note selected on a guitar including a fret-board and strings comprising: a current source; differential amplifier means; counter means for providing a count corresponding to a particular guitar string and to a particular fret position; means responsive to the count of said counter means for gating a current from said current source successively through each string of said guitar and for gating successive voltage drops indicative of the voltage drop across successive pairs of frets of a said string to said differential amplifier means; and means responsive to the output of said differential amplifier means for detecting a voltage indicative of a selection of the note between a particular fret pair and for latching the count of said counter means indicative of the string and fret position selected.

Claim 8

Apparatus for detecting a note selected on a guitar including a fret-board and strings comprising: a current source; differential amplifier means; counter means for providing a count corresponding to a particular guitar string and to a particular fret position; means responsive to the count of said counter means for gating a current from said current source successively through each string of said guitar and for gating successive voltage drops indicative of the voltage drop across successive pairs of frets of a said string to said differential amplifier means; and means responsive to the output of said differential amplifier means for detecting a voltage indicative of a selection of the note between a particular fret pair and for latching the count of said counter means indicative of the string and fret position selected.

Claim 9

Circuitry for detecting selection of a note on a fretboard having a plurality of adjacent frets and a plurality of conductive strings stretched thereover, said circuitry comprising: a shorting string means providing a small but finite resistance between each said fret and grounded at one end; and

Claim 10

Circuitry for detecting selection of a note on a fretboard having a plurality of adjacent frets and a plurality of conductive strings stretched thereover, said circuitry comprising: a shorting string means providing a small but finite resistance between each said fret and grounded at one end; and

Claim 11

differential amplifier means for receiving inputs from a plurality of pairs of said frets and providing an output indicative of depression of a said conductive string across a pair of said frets.

Claim 12

differential amplifier means for receiving inputs from a plurality of pairs of said frets and providing an output indicative of depression of a said conductive string across a pair of said frets.