Blackstar Ht Dual Pedal Schematic Direct

The pedal uses op-amps (often TL072 or similar) to boost the input signal before it hits the tube. This "pushes" the tube into saturation more effectively.

Even when unplugged, large capacitors can hold a high-voltage charge. Blackstar Ht Dual Pedal Schematic

If you are looking at a circuit diagram, focus on these areas: The pedal uses op-amps (often TL072 or similar)

Both halves of the tube are utilized. One half typically handles the initial gain stage, while the second provides additional clipping and drive. Blackstar Ht Dual Pedal Schematic