7400 competition entry: Class D amplifier using digital logic

Class D amplifier using digital logic is the open 7400 competition entry by hasn0life:
The entry is a class D amplifier made entirely out of discrete digital logic components. I took great pains not to use op amps or transistors or any active devices besides logic gates. Though the amplifier outputs square waves, the process to generate them is entirely analog. As such, this design is an example of using digital gates in an analog way.
Check out the video after the break.
This entry was posted in 7400 contest, contest and tagged open 7400 logic competition 2012.

Comments
Nice one! Is there a link for the schematics / documentation??
You can find more details at http://dangerousprototypes.com/forum/viewtopic.php?f=62&t=4733&p=45894 – I should probably learn to make that clickable.