Patent ID: 9167327
Filing Date: 2015-10-20
Classification: H04R

Abstract:
1. A phantom-powered JFET preamplifier gain circuit for a microphone, the phantom-powered JFET preamplifier gain circuit comprising: a first JFET with its gate terminal operatively connected to a positive signal input terminal, wherein the first JFET is operatively connected to a second JFET in cascode having a positive signal output terminal for the phantom-powered JFET preamplifier gain circuit; a third JFET with its gate terminal operatively connected to a negative signal input terminal, wherein the third JFET is operatively connected to a fourth JFET in cascode having a negative signal output terminal for the phantom-powered JFET preamplifier gain circuit; one or more resistors operatively connected to the first JFET and the third JFET within the phantom-powered JFET preamplifier gain circuit; and one or more gain-setting feed resistors external to the phantom-powered JFET preamplifier gain circuit, wherein the one or more gain-setting feed resistors are operatively connected to the positive signal output terminal or the negative signal output terminal of the phantom-powered JFET preamplifier gain circuit.