FIG. 24 shows an improvement to the circuit in FIG. 23 by adding one or more diodes in series to D1 and or D2. By having series diodes, such as D1 in series with D3, and or for example D2 in series with D4, the noise and or distortion as described for the amplifier or voltage controlled amplifier in the previous paragraph pertaining to FIG. 23 is improved. For the circuit in FIG. 24, the number of diodes in series is incremented in terms of integers or of whole numbers. For example, the number of diodes in series can only include N, where N is an element of a whole number such as 2, 3, 4, 5, or the like. For example, there can be 3 diodes in series, 4 diodes in series, etc with the emitter of Q1 and or Q2. Having the nonlinear resistance characteristics (e.g., resistance that changes diode current) in diodes or transistors provide for low distortion (e.g., low harmonic distortion) in voltage controlled amplifier when the signal current is coupled to the emitters of Q1 and or Q2 and when the control voltage is coupled to the base or bases of Q1 and or Q2. If the emitters of Q1 and or Q2 include any linear resistances such as linear resistance in series or in parallel with the diode D1 and or D2, then distortion will increase.
