An interesting Pink Floyd quad antique/curio

[privateuniverse]

Pink Floyd just posted this little curiosity on their Facebook page:

Earlier, we were talking about Pink Floyd's 1987 Momentary Lapse tour, which extended to 1989 (plus a one-off date at Knebworth, 1990). Here's a look at the custom made quad desk used during the almost 200 concerts to control the movement of the surround sound effects around the venues:

 

[Lord British]

I remember seeing them in 1994 at the Silverdome for The Division Bell Tour. They had effects whizzing around the stadium during preshow and I couldn't tell if it was because it was supposed to sound that way or if I was just high as a kite.