Ha yes. Correct. Electrostatic speakers don't use electromagnets, that was incorrect. Mea culpa. They do need a power supply, same as electromagnets, because they use an electrified grid on either side of the diaphragm to move it back & forth. In the big picture not all that different, you're using varying electrical charges to push & pull something to move air. Some of the earliest speakers did use electromagnets, and when natural magnets became widely available, speaker technology really took off because you didn't need a power source. I was thinking about this early state of the tech when I lumped electrostatics into the same bucket.
You know, I sometimes don't give these posts a lot of thought, have had a cocktail or two, and I do apologize for spreading misinformation. I love this site and do it for fun and relaxation, it's not my life's mission, hence my relatively small number of postings. My main point was that certain types of speakers/headphones need a power source and others don't, that much was clear.
But all of your cruel remarks (and not one of you bothering to really explain electrostatics for those people I might have confused) really make me just want to walk away and leave it to the jocks competing for imaginary girlfriends/boyfriends who are turned on by a 500+ post count. If you really want to build a community here why not try a little tact, lift your brother/sister when s/he falls down instead stomping him/her in the face. I'm not competing with anyone here on technical knowledge, just trying to share how much or how little I know after spending 50 years loving music and music technology.
Have a great weekend everyone.
And ps: yes, I am a master at sarcasm, possibly a PhD. How did you know?
Outside of odd drivers like the Heil, and such, electrostats are the only speaker transducers that use no magnets at all, are they not?