Almost authentic tube sound with the FET booster

This mini-booster with field-effect transistors makes the guitar sound quite authentic as with an overdriven tube amp. At lower supply voltage (e.g., 9 volts), there is very little distortion. This can be increased by enlarge the operating voltage, e.g. by connecting two 9-volt batteries in series. If greater distortion is desired, two of these circuits can be connected in series without sacrificing the tube character of the sound.

Overdrive circuit for slightly distorted sounds

This circuit is suitable for creating overdriven guitar sounds. It also includes a kind of treble booster. As a result, it is possible to achieve a differentiated sound even with chords in spite of overdriving. Therefore, the effect is good usable for the rhythm guitar, f.e. at Bluesrock.

The arrangement served as the input circuit of a homebrewed guitar amplifier in the Overdrive channel. In addition, there was also a "clean" channel. Of course, the circuit can also be used for an separate effect device. This then can be supplied f.e. with two 9-volt batteries connected in series. In this case, a bypass circuit is recommended with a footswitch (2x change), as it also can be found in the other effect units presented here.

Distortion effect with diodes and transistors

With this distortion effect, an extremely distorted guitar sound is possible:

Using this effect devce, the lead guitar playing results in a soft sounding. By appropriate playing, it sounds reminiscent of string instruments and you get a lot of sustain. The comparatively low-impedance input flattens the frequency response of the guitar pickup, wich creates a synthesizer-like sound impression. Due to the high gain of the circuit must be paid to good shielding in the guitar electronics, the cable and the construction of this circuit, otherwise hums occur.

A guitar equalizer with switchable crossover frequencies

This three-band tone control is designed for electric musical instruments, especially for electric guitars. Since no exactly linear frequency response can be set, the circuit is not suitable for hi-fi applications. But instead of this, good guitar sounds can be adjusted, if connecting the instrument to equipment that is not intended for this. By switchable crossover frequencies there are many possibilities for customizing the sound pattern. The input circuit with bootstrap feedback provides high input impedance comparable to tube circuits (over 1MΩ).