Zvex Effects Channel 2Your Channel 2 has two knobs, one controlling Master Volume and the other controlling Gain, which sweeps from unity to +24dB. Connect a music equipment power supply of 9VDC, center negative, to the power jack for use. There is no battery in your Channel 2. The Gain control adjusts both the gain and DC bias on the MOSFET transistor at the same time, causing a rushing noise when adjusted. This is normal. At low gains, your Channel 2 has an input