The Tube Zipper Envelope Filter/Distortion Pedal from Electro-Harmonix features a warm sounding Tube Envelope Follower and a rich tube Distortion unit. The Tube Zipper uses two premium 12AX7EH vacuum tubes. The unit features an ENV switch, and a Mode switch that selects Tron/Trill mode. It also features Input Gain, Drive, Sensitivity, Frequency, Resonance and Master Volume knobs. When the Tube Zipper is on, the Power LED will light up. The Status LED lights up when the Tube Zipper effect is engaged, and the Frequency LED gets brighter as the filter's peak frequency rises.
True bypass using a mechanical relay
Overdrive stage allows interaction with the envelope follower for hard hitting sweeps and frequency color
Tron mode allows the filter to sweep smoothly, following your amplitude's envelope
Trill mode allows modulation to be added to the envelope as the filter sweeps
Switchable up or down filter sweep directions
Input gain boosts the signal before the filter drive
Resonance control adjusts the Q or peak of the filter ranging up to self-oscillation