Using this scheme can be made an electronic digital circuit for volume control. The volume control has a maximum range of 63 dB control range. Network R3 + R17 provides fine control in increments of 1 dB, while R20 + R34 network provides gross control in steps of 8 dB. Desired attenuation is fixed with IC1 and IC3 multiplexers, each controlled by three digital inputs.
Maximum input level should not exceed 20 V in amplitude, which is 14Vef.
Amps circuit is mainly determined by dual operational amplifier and is about 10 mA.