When I was a teenager I was friends with an extremely poor kid who literally lived on the wrong side of the tracks. He couldn’t afford a microphone and used an old pair of busted headphones to rap into as a microphone. He had recorded and produced a whole album like this with Fruity Loops on an old computer he found discarded at the side of the road.
My little brother and I did this with an old Panasonic tape recorder. We were in elementary school so it wasn't very good, but it got my brother into music production.
What do you think? He was poor in America, so he stayed poor in America. 99.999% of stories about people in hopeless poverty end with them in hopeless poverty. To expect otherwise is ludicrous.
A fun fact is that the ability of a single transducer to function as both a speaker and a microphone is the basis for establishing an absolute measurement of sound pressure.
I have vague memories of iPod Linux (or Rockbox, I can’t remember) having a feature where you could record voice notes using your regular headphones using the same technique
Not sure if it's mentioned in the article but microphones can be speakers too...
Only dynamic mics, which are relatively rare and seldom encountered without an attached preamp. The vast majority of mics for PCs are condensers and electrets.
Anything can be a speaker, briefly and only once, if you apply enough voltage to it...
I think you have this backwards. Condensers and electrets (a form of condenser with a permanent charge on one terminal) almost always have a built-in preamp. The reason is that they cannot drive a capacitive load of any magnitude, and their outputs must be buffered before being fed to any wiring.
Like another post mentioned, dynamic mics like the Shure SM58 mentioned here, can drive a cable directly or through a small built-in transformer. They're still used in live sound, though condensers have become quite common there too. Condensers still tend to have somewhat better behavior, such as signal-to-noise, than electrets.
Of course everything has to be amplified or fed to a digitizer at some point. The issue is where the preamp needs to be physically located.
I recall when I was a kid decades ago, being able to plug a speaker directly into the microphone jack and use it as a microphone, without any modifications whatsoever.
We could do the reverse too, plug a microphone into the speaker jack and hear sounds coming out from it.
What’s wild is that most things having to do with light, magnetism, and/or electricity are interchangeable and reversible. Put electricity through a wire and it’ll create a magnetic field, or wave a magnetic field near a wire and it’ll create electricity. That means that putting electricity into an LED creates light and a magnetic field, or putting light into the LED creates electricity and a magnetic field, or waving a magnetic field near it will create electricity in the wires and light from the LED. Granted for that last one you’ll need a spinning magnetar nearby, or just add some more wire to the LED and it becomes a kitchen counter experiment.
Same interchangeability with solar panels, transformers, thermoelectric devices, etc. The effect might be big or small, depending on the setup, but the physics is happening either way.
I’ve spent time lost in space thinking about how much stuff is really just a copper wire in various configurations.
Have a copper wire - it’s an antenna, magnet, inductor, fuse, thermometer, heater, and strain gauge.
Put another copper wire near it - it’s a capacitor.
Curl one more than the other - it’s a transformer.
Put iron on it - it’s a thermocouple.
Put electricity through it - it’s a peltier cooler.
Add salt water - it’s a battery.
Put electricity through it - the iron is now a permanent magnet.
Wave the permanent magnet near it - it’s a generator and a microphone.
Put electricity through it again - it’s a motor and a speaker.
Heat it up and it’ll make Cuprous Oxide - it’s a solar panel and a diode.
While staying in a high-end D.C. area hotel, I once discovered a hidden hard-wired speaker under the bathroom sink. Somebody had written "F.B.I." on it with nail polish.
I already knew that speakers could be used as microphones, and it occurred to me that putting a speaker in a hotel room in the name of "safety" would be a great cover story for a surveillance operation.
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You had me for a second :)
https://nvlpubs.nist.gov/nistpubs/jres/25/jresv25n5p489_A1b....
[1] https://bobbyowsinskiblog.com/build-subkick/
Not sure if it's mentioned in the article but microphones can be speakers too...
Only dynamic mics, which are relatively rare and seldom encountered without an attached preamp. The vast majority of mics for PCs are condensers and electrets.
Anything can be a speaker, briefly and only once, if you apply enough voltage to it...
Like another post mentioned, dynamic mics like the Shure SM58 mentioned here, can drive a cable directly or through a small built-in transformer. They're still used in live sound, though condensers have become quite common there too. Condensers still tend to have somewhat better behavior, such as signal-to-noise, than electrets.
Of course everything has to be amplified or fed to a digitizer at some point. The issue is where the preamp needs to be physically located.
These can be run in reverse as well, it requires CB custom electronics so it’s not something a lay person can do out of the box.
But you probsbly think about smaller form mics like found on headsets (Electrets).
We could do the reverse too, plug a microphone into the speaker jack and hear sounds coming out from it.
Same interchangeability with solar panels, transformers, thermoelectric devices, etc. The effect might be big or small, depending on the setup, but the physics is happening either way.
I’ve spent time lost in space thinking about how much stuff is really just a copper wire in various configurations.
Have a copper wire - it’s an antenna, magnet, inductor, fuse, thermometer, heater, and strain gauge.
Put another copper wire near it - it’s a capacitor.
Curl one more than the other - it’s a transformer.
Put iron on it - it’s a thermocouple.
Put electricity through it - it’s a peltier cooler.
Add salt water - it’s a battery.
Put electricity through it - the iron is now a permanent magnet.
Wave the permanent magnet near it - it’s a generator and a microphone.
Put electricity through it again - it’s a motor and a speaker.
Heat it up and it’ll make Cuprous Oxide - it’s a solar panel and a diode.
Put electricity into it - it’s an LED.
> perfectly sound.
I hear what you did there
I already knew that speakers could be used as microphones, and it occurred to me that putting a speaker in a hotel room in the name of "safety" would be a great cover story for a surveillance operation.