Milan Digital Audio LLC (Shareware)

Hauptwerk is a virtual instrument designed by Milan Digital Audio and released on April 2011. The program specializes in pipe organ music through sound samples from hundreds of real pipe organs. Input is from a MIDI device, which could be a MIDI sequencing program or an external MIDI keyboard. The program converts the MIDI input into an audio signal, which is then converted into an audio output based on the particular pipe organ sound used as sample. This program features more than 50 pipe organs all over the world that users can choose from.

Hauptwerk recorded samples are made up of three parts—attack (start), sustain (middle), and release (end). A note will play starting from the attack, then the sustain playing in a loop. As soon as the note is released, the echo section or the release is then played. The echo section of a particular pipe organ is also affected by the duration of time it has been played. Thus, this program offers multiple release samples to mirror that effect. This virtual instrument features harmonic filtering effects normally done through an Expression pedal controlled by the organist. This creates an effect on the frequency envelope and the volume of the pipe sound. The Hauptwerk also features Fluid dynamics, which deals with the wind pressure affecting the pitch, volume, and character of the sound.