Treble and Fuzz

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The Distortion/Treble Booster box is finished. It's very compact and easy to use, having only two controls, a power switch and an o/p level adjustment knob. It was a challenge trying to source a suitable stomp switch, but I eventually got one on Ebay from China, which is just the correct size and height, with it's multiple contacts allowing the unit to be operated in 'true bypass' mode, with the I/P completely isolated from the O/P when the foot- button is deactuated. The circuit itself draws only 150 Microamps of current, from a 9V PP3 battery, so I calculate that if the Axe Man forgets to turn off the power for 8 weeks, the battery will still produce 7.5 Volts, which is enough to operate the system. As for the sound; well it's awesome. Those guys, back in the 60s knew a thing or two about guitar effects. Of course, the idea of using a germanium transistor was purely accidental, as they were the only solid-state devices on offer at the time. However, it was fortuitous that it produced the results that it did, and all because of a basic weakness in the semiconductor technology of that era, namely that the germanium transistor exhibits a reduced gain, or hfe, when the input signal level increases substantially and drives the base current towards zero, leading to an unusual sounding compression and soft clipping of the audio signal output. This weakness was exploited to the full in the original 'Dallas Rangemaster' design, of which this stomp box is a copy, or indeed a clone, in terms of circuit design and component values anyway. Long live Rock and Roll.