1. of interest to any people with ipod earbuds:

stick them in your mic input on your computer, and you can use the left earbud as a microphone. very handy in a pinch, and it also sounds fine through line in

Posted at 11:02PM on Oct 27th 2007 by peter hajas

2. @1
Or anyone with any other earbuds - they all are pretty much the same.

Posted at 11:51PM on Oct 27th 2007 by gm

3. i once saw a guy from Shure re-wire an sm58 as a tiny speaker as a demonstration of this very concept.

I especially like that he's wired it up to be more than just a mic.

Doing cool shit with junk is awesome.

Posted at 11:52PM on Oct 27th 2007 by lonas

4. ahhhhhh the oldest trick in the book

Posted at 1:41AM on Oct 28th 2007 by alex mccown

5. Hmmm, not so sure about using headphones as a PC mic, The PC provides a DC voltage to the right bud, I guess that others here might know if that DC voltage was enough to overheat the bud over time.

Posted at 5:25AM on Oct 28th 2007 by Will

6. Hmm, might have to try this with the Sub from my Logitech Z2300's when i get my Z5500's

Posted at 6:48AM on Oct 28th 2007 by EthanV2

7. While this is very cool, I am beginning to find the instructables website rather annoying.

Posted at 7:43AM on Oct 28th 2007 by Bhima

8. open headphones work reasonably well as a microphone

Posted at 8:46AM on Oct 28th 2007 by Wesley

9. I was using speakers as microphones back in 1980. I accidentally discovered it playing with my brand new state of the art cassette recorder. I actually got better sound of the speaker than I ever did any mic that I could hook up to it AND it was significantly more sensitive. I used it to record my parents talking with my uncle 2 rooms away and I couldn't physically hear them at all with my ears but I could hear them loud and clear through the recorder. Since then I've used speakers as microphones several times, even recently.

Posted at 11:37AM on Oct 28th 2007 by eric

10. will: you can solve the dc voltage problem by putting a capacitor in series with the headphones.

Posted at 11:39AM on Oct 28th 2007 by eric

11. I saw this in... "Honey, We Shrunk Ourselves"
http://www.imdb.com/title/tt0119310/
I believe, in his midget status, he scrapes some of the solder off, which does some funky film magic and makes it a microphone...

Posted at 11:51AM on Oct 28th 2007 by Will

12. this has been a common dj trick since the late 70s... if you dont have a mic at your mixer, just plug your headphones into the mic jack, make your announcement, and plug em back into the cue jack.

Posted at 5:33PM on Oct 28th 2007 by samurai

13. All hail transducers!


yay

Posted at 7:03PM on Oct 28th 2007 by strider_mt2k

14. Wow, I mean just wow. In other news, water can be used for drinking AND bathing!
Seriously, folks. Take apart an old microphone from the 50's; it's a speaker!
Remember in grade school how the PA system speaker was also a microphone?
This goes waaaay back to when they actually were the same thing; I even have an ancient bakelite telephone where instead of the mouthpiece having a carbon mike, it'...just another speaker!

So as to not just gripe and groan;

Other uses for speakers and/or microphones:
-Poor man's laser show:
lay raw speaker on back.
lay a mirror on it so that one end is supported by the speaker.
Aim laser pointer at mirror onto ceiling. play music.

-Poor man's actuator:
-strip most of the cone off or make holes so that air movement is reduced.
use to move parts of halloween display, such as eyelids or lips.
recorded speech makes a good signal source.

-passive (resonance) amplifier / frequency selective microphone:
-take Aluminum tubes about 1/4 inch in dia, cut to various lengths. Bundle together.
attach speaker to end of bundle (air tight, please).
Each tube if cut carefully will amplify a single frequency only, picked up by the speaker.

Posted at 2:31PM on Oct 29th 2007 by Scrappylaptop

15. Just think, if someone had discovered this 45 years ago, Jack in the Box might have pioneered the drive-up window...

Posted at 2:47PM on Oct 29th 2007 by Stephen-C

16. "Hmmm, not so sure about using headphones as a PC mic, The PC provides a DC voltage to the right bud, I guess that others here might know if that DC voltage was enough to overheat the bud over time."

Shouldn't be a problem. Typically it's only a 5V bias designed to drive the electret microphone pre-amp at ca. 1 mA. I would be surprised to find a commercial device that does not have some kind of current limiting in case of a short circuit.

Posted at 5:10PM on Oct 29th 2007 by Marco

17. This is a classic 'hack'.

Since I have virtually no cash, I use a car speaker (found in trash, of course) as my main mic. It sounds terrible, but alright for rough demos. From a 4 track tape recorder.

Posted at 3:11AM on Oct 31st 2007 by neoxide

18. after looking at the circuit, i wonder about impedance of this device since the transformer is a 1:1 and the coils are 4 ohm each. does it react favorably with preamps, and how would it compare with commercially manufactured mics?

Posted at 11:24AM on Oct 31st 2007 by cliff