Providence - HBL-4 Heat Blaster

The internal circuit doubles the supply voltage from 9 volts to 18 volts, resulting in a wider dynamic range and a sound more like an amp than conventional distortion effects.

In a normal True-Bypass circuit, in bypass mode, the audio signal passes through two switching contacts. But in the HBL-4, in bypass mode, the audio passes through a single contact, thanks to a single-contact true-bypass circuit.
The result is sound quality and reliability far superior to those provided by existing products.

The S.C.T. Circuit now further reduces any change or deterioration in sound quality and gives the feeling that the footswitch circuit is completely removed from your signal chain.

Due to the adoption of the new Dual Contact Grounding Circuit (D.C.G. Circuit), by inserting a mono plug into the output socket, the shield (sleeve) of the plug provides two points of contact with the pedal ground circuit.
By increasing the surface area of the contact point, it becomes more difficult for a loose connection to occur, and offers the added benefit of improved sound quality.

As well as indicating the on/off status of the pedal, the HBL-4's LED provides effective visual monitoring of battery power. When the battery voltage drops below 7 volts, the LED dims and begins to fade.
The effect will still work at this voltage, but to ensure optimum performance, the battery should be replaced as soon as possible.