Developed by students at the University of Ulm in Germany, the Timbap DJing interface uses an acoustic timecode signal from a vinyl record to allow a user to select skip tracks, scratch and otherwise manipulate digital audio from the familiar turntablist perspective. But instead of being limited to one LP the user’s entire music library is navigable -

The rotation of the turntable serves as a means for scrolling through the music collection automatically. The user stays in control though and can always intervene manually – for example by holding the record or winding it back. In order to provide goal-oriented search, we also support a direct absolute positioning using the tone arm.
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There are several visual cue types available. They are always combined with a sorting method. In the first picture you see the standard type which is an alphabetic index of artist names. The display size of the initial characters is proportional to the number of contained mp3s. When the projected size of the whole cue has been calibrated to go from the first groove to the last groove of the record, the index will be surprisingly precise. This way, you will only need a few needle resets to find the track you are looking for within hundreds of mp3s.

– Timbap