Wizoo, the developer of the Steinberg Hypersonic virtual music workstation, has unveiled a free extension for Hypersonic.

The Hypersonic GM-4 expansion is a free upgrade for all Hypersonic users and adds GM (General MIDI) functionality to Hypersonic, including 128 GM compatible patch programs, a GM standard drum kit and an additional 110MB (330MB uncompressed) of new sample content.

The GM-4 Module can be downloaded for free at http://www.wizoo.com.