CHAPTER 14
Balance Controls
The Ideal Balance Law
The job of a balance control on a preamplifier is to adjust the relative gain of the left and right channels and so alter the position of the stereo image to the left or right and do nothing else at all. As you would expect, increasing the left gain moves things to the left and vice versa. The ideal law is therefore that of a stereo panpot in a mixing console. Two uncorrelated sound sources (and any signal will be uncorrelated once it has left the loudspeakers and bounced around the room a bit) add just like white noise sources and so give a combined signal that is 3 dB higher and not 6 dB higher. The sine/cosine panpot law in Figure 14.1 is therefore appropriate for the balance control of a ...
