AW: Re[2]: home-made vca

[Haible Juergen]

>      The Analog Devices app note for the MAT-04 quad matched NPN hints that
>
>      the biggest effect of transistor mis-matching in VCA designs is
>      distortion.

Hmm, but even with perfectly matched transistors, you got this principal
nonlinearity - was it a tanh(x) or something like this ...

The specs for their example circuit are as follows:
>
>      Frequency response - 20Hz-20KHz flat
>      Noise level - 110dB below full output
>      Distortion - under 0.03%

Does this apply to a simple differential pair input structure, or are
you talking about a linearized circuit?

JH.