» The Robotalk2 sports two individual envelope filter channels. Each channel isindependently voiced and can be preset for different playing style; slow acoustic-like attack,percussive, high speed open-close and many more. Blend each channel together for additional tone or use the internal dip switch to customize your sounds appropriately. There's a switchable input pad for accommodating both active and passive signals. » True bypass for eliminating any signal interference when switched off. Can be used with AC adaptor (optional) or 9V Battery.