Keyer circuit

Claim 1

IN AN INDIVIDUAL PERCUSSION KEYER CIRCUIT FOR A MUSICAL INSTRUMENT FOR USE WITH A RESPECTIVE INDIVIDUAL MUSICAL TONE SIGNAL SOURCE REPRESENTATIVE OF A SINGLE MUSICAL NOTE TO CONNECT THE RESPECTIVE SOURCE TO AN OUTPUT SYSTEM COMMON TO A PLURALITY OF INDEPENDENT SUCH SOURCES UPON THE ACTUATION OF A RESPECTIVE PLAYING KEY, AN ELECTRONIC VARIABLE IMPEDANCE DEVICE THE IMPEDANCE OF WHICH IS DEPENDENT UPON THE POTENTIAL APPLIED TO A TERMINAL THEREOF, CIRCUIT MEANS INCLUDING SAID VARIABLE IMPEDANCE DEVICE FOR CONNECTING SAID SOURCE TO SAID OUTPUT SYSTEM, MEANS NORMALLY APPLYING A BIAS POTENTIAL TO SAID TERMINAL TO RENDER SAID CIRCUIT MEANS INEFFECTIVE TO CONDUCT SAID SIGNAL TO SAID OUTPUT SYSTEM, MEANS INCLUDING THE PLAYING KEY FOR APPLYING A PULSE TO SAID VARIABLE IMPEDANCE DEVICE TERMINAL IN RESPONSE TO ACTUATION OF SAID KEY TO CHANGE THE POTENTIAL AT SAID TERMINAL SUBSTANTIALLY INSTANTANEOUSLY TO RENDER SAID CIRCUIT MEANS EFFECTIVE TO CONDUCT SAID SIGNAL TO SAID OUTPUT SYSTEM, AND AUTOMATIC MEANS OPERATIVE WITH THE APPLICATION OF SAID PULSE TO REESTABLISH SAID NORMAL BIAS POTENTIAL TO SAID TERMINAL AT A SLOW RATE FOLLOWING THE APPLICATION OF SAID PULSE TO SAID TERMINAL FOR PROGRESSIVELY RENDERING SAID CIRCUIT MEANS INEFFECTIVE TO CONDUCT SAID SIGNAL TO SAID OUTPUT SYSTEM.