Patent ID: 8704074

Claim:
A noise cancellation system for existing electric stringed instruments comprises of a pickup circuit with a single or plurality of pickup coils named signal coils; each of the said signal coil not only senses the vibrating strings, it also senses unwanted electromagnetic radiation; thereby, each produces a noise voltage that causes humming and buzzing noise when connected to an amplifier; the said noise cancellation system together with the said pickup circuit comprising: a means of noise sensing that senses only the said unwanted electromagnetic radiation; and one or more transconductance means with high output impedance, each transforms the output of the said means of noise sensing into a current signal; said transconductance means injects the said current signal directly into one of the said signal coil; high output impedance of the said transconductance means allows direct connection to the said signal coil with negligible affect on the total impedance loading the said signal coil; whereby, preserving the sound characteristics of the said existing stringed instrument; one or more transimpedance means, each comprises one of the said signal coil in parallel with the impedance of the circuit loading the said signal coil in the said existing stringed instrument; each of the said transimpedance means transforms one of the said current signal back to a voltage equal and opposite to the said noise voltage from the said signal coil; whereby, canceling each other and eliminating the noise.