Verbos Electronics - Amplitude and Tone Controller
In 1971 the arp 2600 provided an all discrete vca with simultaneous exponential and linear control. the normals put the exponentially curved ar envelope into the exponential cv input. this "super exponential" response makes for great percussion sounds. the arp vca and other vcas like it cannot add cv on one input and subtract it on the other. the verbos electronics amplitude & tone controller has overcome this problem. the front panel amplitude control is connected to the linear cv input, but it can be turn up and a cv sent into the exponential cv in and the reversing attenuator turned router clockwise to fade the volume down.
the amplitude & tone controller is a totally discrete vca with simultaneous exponential and linear cv input. it has a discrete output stage, too. but it also is an all discrete vactrol based voltage controlled lowpass filter with diode limited resonance. it also has a discrete gain stage on the input. careful balancing of the input gain and resonance control sets a mix of self oscillation and input signal, distorted on the vca input as you wish. no ics anywhere in the signal path.
with a tweak of the "freq. c.v." input and "exp. c.v." input (normalled together) the famous "combo mode" of lopass gate fame can be achieved. the addition of resonance and the separate of the lopass and amplitude control allows much more.
16 HP width
26 mm depth with power cable attached
power consumption: 30mA +12, 20mA -12