This digital mixer uses CMOS integrated circuits. The circuit was published by us in a magazine with which we collaborate. Signals should be of low intensity (mV) from a source such as a microphone, pickup or preamp. The input and output cables must be shielded. Changes in C1 must be made if there are switching noises. Note that the power supply must be symmetrical. The source must have excellent filtration. Two similar units should be used in a stereo version and the source may be unique. Also, two units can be connected in parallel to a mixer 4 channels.
