Select 2

Two accurate gate-controlled voltage processors in 6 HP, to create, switch, mute, hold, invert, attenuate, offset, mix and subtract voltages from slow control voltages up to audio. Each processor has two signal inputs: the left one is used by default, and a gate on the select input switches to the right one; unpatched, they are normalised to a precision +5 V reference and to 0 V. A hold circuit follows: a rising edge on the hold input freezes the voltage until the gate goes low again, and its low-droop design keeps a held voltage accurate for several minutes. The last stage is a gated polariser: the knob sets the gain from -1 through 0 at the centre to +1, and a gate on the unity input bypasses it. Dual-colour LEDs show each output voltage, and with the A output unpatched its signal is mixed into the B output, for offsetting, CV mixing or pitch transposing.