heironymouscoward's Journal: MDPA/4

Speaking to a friend who's a trance-techno DJ, he's hurting because vinyl is getting so expensive. 10 Euro, he says, for a 5 minute piece. But a working DJ needs dozens of these each week, always the latest and newest stuff.

Pioneer have a cd-based turntable that DJs like, but it's not the same. Good, yes, but it's not as good as vinyl.

So, this prompted MDPA/4. The concept is a modded dual-platter turntable, consisting of:

  - laser diode and reader mounted on the needle heads
  - rotation sensor on the playback arms
  - internals augmented with a digital music player
  - small touch screen allows selection of left and right tracks

The original audio circuits are completely disconnected, although in principle they could be left in place for the fun. The laser diode and rotation sensor tracks the movement of the head across the vinyl and this movement (track play, skip left/right, back, slow/fast) is translated by the media player into a realistic simulated sound.

If the DJ picks up the needle and drops it again a few tracks further, the digital playback follows. If the DJ scratches the music, the playback scratches. If the DJ slows or speeds up the record,... you get the picture.

The advantages of this design? The DJ gets a pure vinyl feeling, finger-tip control over that glorious black plastic. The record companies and artists producing the original pieces have a much cheaper distribution mechanism.

Implementation of the media player: probably needs to be based on a lossless compression format (even WAV files), and using a harddrive for storage. The use of a lossless format may help with the main problem, which is to ensure a perfect playback with no noticeable lag.

The player would have to be calibrated for a particular vinyl. This is done simply by playing the record once, so that the needle and rotation sensor can track and map the surface. This mapping can be overlaid onto the track being played so that a perfect match can be made between the position of the playback head, and the portion of music being played.

Optional extras: a CD reader which loads tracks of a CD, digitises them, and adds them to the database for later selection.

Price: should be doable for about $200-400, depending on the amount of storage provided.