The Tesseract" DIY Guitar Practice Amplifier is an LM386 based low power amplifier designed to deliver up to about 500mW into an 8 Ohm speaker when run from a 9V battery.

Selectable Bipolar or Junction FET input stage for different input overload effects;

Adjustable gain and clipping 'hardness' in the Distortion stage;

An adjustable fullwave rectifier stage, driven by the distortion output, that generates a type of fuzz and frequency doubling effect called 'Wreckage';

An optional low frequency oscillator stage to sweep the Wreckage effect;

A simple mixer to blend the 'Wrecked' and the 'Distortion' outputs;

Selectable, adjustable low or high frequency boost (a type of tone control);

An important aspect of the design is that all the features and FX can be tweaked for your delight and delectation.

Most features are also optional and can be wire linked out if not required without affecting the other functions.

The design could easily be modified to suit the LM380 2.5W or LM384 5W amplifier chips (although the Boost function would have to be omitted) or a range of other devices.

The design also includes a headphone output jack.