Building Your Own Drivers? 34
students asks: "I want to cheaply demonstrate how speaker 'drivers' (the part that makes the noise, not software...also known as a cone) work, not to produce ideal sound. Some quick research has made it clear that it's easy to find directions on how to build a fancy speaker box, but not much on how to make a driver. Unfortunately, I can't use Sake. I also can't get the thin wood. Does anyone know how to build a driver out of home materials?"
You just need some hard drives (Score:5, Funny)
Seriously tho (Score:3, Informative)
Solenoid (Score:2)
Re:Solenoid (Score:2)
Re:Solenoid (Score:1)
Sure. Here you go. (Score:5, Informative)
Re:Sure. Here you go. (Score:2, Funny)
I didn't even know that place was real.
-Peter
Re:Sure. Here you go. (Score:2, Funny)
Build your own driver (Score:5, Informative)
Simple science-type experiments are super easy to do. No more complex than an electric motor experiment.
Although I haven't read it, this [howstuffworks.com] probably has everything you need.
Re:Build your own driver (Score:3, Informative)
Voice coil motors are not limited to audio work, however. One notable example is the replacement of stepper motors in hard drive head positioning systems.
Not all voice coil operated lo
Pictures say a 1000 words (Score:3, Informative)
You will have to create your own motor (magnet + former), your own cone and your own suspension (spider and suround)
get a few donut shaped magnets amd glue them together, a paper tube wrap some thin magnet wire around it secure it with epoxy. get a hunk of round steel and a thin plate. attach the steel to the center of the plate, put the magenets around the pole peice and attach to the plate. add another steel plate to the top with a hole big enough that the former fits in.
thats your motor
make a spider from something. get a paper cone and attach it to the spider to the former to the surround to the frame. and your done !
Or, you can get a cheap $10 speaker from partsexpress.com and use that as an example with good drawings
Re:Pictures say a 1000 words (Score:3, Informative)
EASY! (Score:3, Interesting)
That's a simple speaker and how many of the really cheap ear-phones work.
Here's an example... (Score:3, Informative)
just vibrations (Score:1)
9th and 10th grade science lesson (Score:3, Informative)
FP link is broken, I fixed it (Score:2)
Enjoy. And give 'em slashdot's best.
Easy! (Score:2)
Just be careful removing the bottom steel plate so you don't damage the coil. Easiest way is to use a nail or sharp knife to scrape away as much of the glue as possible then brace it in a vice and use a cold chisel or large standard screwdriver to pry/knock it loose.
Once the bottom plate is off use that same chisel comi
Building drivers is easy... (Score:4, Funny)
make
make install
Someone had to do it
Re:Building drivers is easy... (Score:1)
Re:Building drivers is easy... (Score:2)
Ohh.... you treading in scary waters there....
Let me tell you how I did it... (Score:3, Interesting)
I started out with a largish cardboard box, and traced a large circle on the front, and cut it out with a steak knife. I then made a paper flattened "cone" out of construction paper (a little larger than the hole), made a bunch of radial slits along the edge, then bent, formed, and glued this to the hole. At the apex of the cone (inside the box), I had glued a piece of toilet paper tubing upon which I had wound a mess of wire I had gotten from the windings on a motor armature (as I remember, I didn't do a very neat job of winding it). On the backside of the cardboard, underneath the tube, I mounted (with a bunch of duct tape) a piece of speaker magnet I had (for some reason, when I was a kid, it was far easier to get speaker magnets than whole, large speakers - but I digress). I hooked the wires from the coil up to a radio - and it worked!
Not much bass, but it was definitely a working "loudspeaker". You could probably take this same technique and apply it to build a much better speaker, perhaps even something to act as a demonstration model. With a little thought, you could even put together a bunch of "speaker kits", if you are teaching a class or something...
These folks cater to speaker builders (Score:2, Insightful)
In particular: here [partsexpress.com]
There seem to be howtos, free design software, parts, etc.
I'm not associated with this site, other than as a customer. (Inexpensive optical audio cables!)
Mr. Wizard (Score:2)
Work hard on the drivers... (Score:1)
Alright, (Score:2, Interesting)
Now, to get a decent shape, suspension, and spider for your speaker, you may want to make your own paper and mold it onto the shapes.
Start with Play-Doh® or something similar. Shape out the cone and suspension nicely. Then, make a plaster (flour, if need be) cast of it. Then cast that, and seal the result. Now you have a mold to form your cone. Do the same with the design for the spider. The great thing about this proces
Do you NEED an electomagnetic speaker? (Score:2)
It sounds like you're doing something Mr. Wizard-ish, where you'll be showing younger kids "how stuff works". So maybe you don't need to build a speaker as we know it.
Back in the day, when dinosaurs ruled the planet, we had these things called "LP"s and "45"s. And when we were young, we always used to fool around with them, doing things that would make our college audiophile friends scream. Including ...
... playing the records by rolling a sheet of paper into a cone, sticking a pin through the small en
Better lesson - use old speaker (Score:5, Interesting)
Next I take a cheap sine wave generator (you can get kits that cost $10) and set the frequency to maybe 5Hz (you can find cheap multi-meters that measure Hz). The point here isn't to listen (you can't) but to see the cone moving in and out. This helps the student see that the signal going to a speaker is alternating current (AC) and it quickly moves the speaker back and forth. Higher frequencies move the cone so little or so fast that it's difficult for the student to understand what's happening. So starting with a low frequency and then turning up the frequency helps the student see exactly why the speaker is making sound. The bigger the speaker the better this demonstration works. I usually had 15" drivers to mess with and you can really see the cone move at frequencies below 20.
Have fun.