There's always a Halloween gig or two, and a visual effects can be fun. Here's some ideas to grab an old speaker to make a poloidal vortex ring. A slow moving vortex ring filled with smoke that shoots out from the band. Throw air against air and you get a vortex.
A well designed cabinet would never chuff a vortex out. Major speaker companies have lawsuits against each other as they try to minimize vortices and turbulence in ports. Vortices cause noise and doppler problems as well as rob port efficiency. However, You can force a cabinet to chuff some air by applying a low frequency ramp waveform. Fill a chamber with smoke or Dry fog, pull the cone back slowly then shoot it forward to puff out air. This puff carries the smoke in the form a ring. You need to pull the cone back again because the vortex has just as much air moving forward as it does backwards.
Here's a youtube of a home vortex cannon
Have some fun with it, just don't over do it!

A well designed cabinet would never chuff a vortex out. Major speaker companies have lawsuits against each other as they try to minimize vortices and turbulence in ports. Vortices cause noise and doppler problems as well as rob port efficiency. However, You can force a cabinet to chuff some air by applying a low frequency ramp waveform. Fill a chamber with smoke or Dry fog, pull the cone back slowly then shoot it forward to puff out air. This puff carries the smoke in the form a ring. You need to pull the cone back again because the vortex has just as much air moving forward as it does backwards.
Here's a youtube of a home vortex cannon
Have some fun with it, just don't over do it!
