Why is my plasma Ball so dim?

Can I use a plasma ball to generate sound? (Like a plasma speaker.)?

• Answer:

  plasma speakers generate sound by heating air that's in contact with the plasma. When air heats up it expands and the amount/rate of expansion controls the sound intensity/frequency. plasma globes are inside a glass container, (due to being low pressure arcs/corona discharge). They do heat up but the glass slows down heat transfer to air, and so I'd say you need a way to get the arcs outside the glass. It sometimes possible to induce an arc to form outside a plasma globe, by placing a conductive surface on part of the globe, and having an earthed conductor a little distance away from that. If that arc can be modulated at audio frequencies then you've got a speaker. Possible modulation techniques could be a electromagnet field applied across where arc would form. Probably easier using a solenoid to move the earthed conductor back and forth towards the globe.