The Morning Glory V4 features Volume, Drive, Tone and Gain switches. The Volume control controls the overall output level. The Morning Glory V4 adds twice the headroom compared to the previous model. The Drive control increases distortion when turned clockwise, and increasing this control also slightly enhances the treble. The Tone control is a basic high-pass filter. Turning it clockwise brightens the tone, while turning it counterclockwise darkens it. The Gain toggle switch activates a new Boost mode, which is powerful and emphasizes low end. You can also increase the Drive knob for even higher gain. The LED turns red when in Boost mode. The Gain toggle switch can be remotely controlled using a latching footswitch connected to the terminal on the side. Connect a mono plug to the red terminal on the side and operate it with a latching footswitch. When a plug is connected to this terminal, the Gain toggle switch on the unit is disabled. Morning Glory is an exceptionally transparent tone-shaping tool, based on the original Masrhall Bluesbreaker, and the result of years of building, gigging and refining. The Morning Glory has evolved significantly while retaining the original goal of the designers of the legendary BB. From the bell-like ring of "Little Wing" to classic rock distortion and even higher gain using the Boost mode. Strat players will discover sounds they never thought possible, and Les Paul players will discover a new sonic palette that they won't be able to live without. The high headroom is highly effective not only when used for distortion but also when used as a clean boost. Morning Glory V4 is powered by a standard 9V adapter and cannot be powered by batteries. Current consumption is less than 100mA.