The QuietConduit cable design incorporates several refinements over normal balanced cables. A conductive polymer interface layer between the braid shield and the insulation of the signal conductor short-circuits triboelectric currents where they are generating, virtually eliminating microphonic noise pickup. A secondary benefit of this layer is to improve the electrostatic shielding effectiveness of the braid shield. Another crucial improvement is the elimination of drain wires, which is normally included for ease of termination but which allow shield currents to couple noise asymmetrically into the signal conductors. The geometry of the QuietConduit cable is precisely controlled, insuring that any noise coupling is strictly limited to common mode.