I just read this article on graphene speakers, which use oscillations in heat energy that create air pressure changes and therefore sound. I'd be interested to hear how it sounds.
audioaudio90 Messages: 623 Registered: October 2010
Illuminati (1st Degree)
I would like to hear it too. Being able to put a speaker on such a flexible substrate would be useful, but it's got to be able to faithfully reproduce the frequencies, and since he's only run milliamps across it, I want to know how well it works at higher currents.
That is interesting. I can see how it works, since air molecules move further apart when heated and closer together when cooled, so you could get the pressure changes needed for sound. I wonder why no one has thought to try this method before.
Wayne Parham Messages: 18791 Registered: January 2001
Illuminati (33rd Degree)
This is completely unrelated, but is another interesting alternate technology. Two ultrasonic carriers signals are used, with one shifted so the beat frequency of the interference is modulated to form an audio signal in the 20-20kHz range.
audioaudio90 Messages: 623 Registered: October 2010
Illuminati (1st Degree)
Wayne, I understand how the beat frequency is created, but I'm not sure what beam steering is. Does it mean they change one or both of the ultrasonic frequencies to vary the beat frequency?