ageedizzleDo smoke detectors have little speakers inside them? If yes, would it be possible to hack them to play a little jingle?
gedaliyahUsually it’s not exactly a speaker, but it does involve a controlled moving diaphragm. In a piezoelectric buzzer, a current applied to the diaphragm causes it to oscillate, and the size and shape of the diaphragm determines the tone AFAIK.
It may be theoretically possible to engineer such a device into a rudimentary speaker. I mean, people have done it with Tesla coils and player pianos, so hey, anything is possible?
CameronDevYou can also make hard drive heads play music. Poor quality music, but music.
Multiple piezoelectric buzzers could probably play a tune if you tune them to individual notes. Not sure how to tune them, but probably cutting them, or putting bluetak on them would alter their note.
You can also make hard drive heads play music.
How does this work?
A basic speaker is functionally a copper coil next to a permanent magnet. A hard drive head (although I guess more specifically read arm?) is also a copper coil next to a permanent magnet. So if you push an audio signal through the coil, it vibrates and makes sound. It’s missing the diaphram/cone part of the speaker, so it’ll be very tinny.
If you want to make one yourself, get a broken hard drive, and an old pair of headphones, and connect the wires to the coil and play some music.
Hard Drive Speaker - More Instructive Version
Hard Drive Speaker - More Instructive Version: So, you found/scavenged/broke a Hard Drive, and want something more constructive to do with it than make the platters into a wind chime, or just beat the thing to death with a hammer? You've come to the right place! I actually made mine a year or s…