The DTA is a high quality, fully discrete transistor based VCA designed by Manhattan Analog. The ‘Drive’ control is a simple input attenuator. At higher settings the audio input can really overdrive the module, depending on its amplitude obviously. The saturation happens at the input, so you can set the timbre as you like it with the ‘drive’ control and the VCA modulation/output level won’t change the drive character. From there it gets a little bit more interesting. This isn’t one VCA, it’s two in series and you have to open both of them to get any output. ‘CV’ is the control signal input for the first stage, ‘Volume’ is the control signal input for the second stage. Both controls have +V normalled through the jacks so you can still open the VCA(s) without any external inputs