A paper plate speaker for less than a dollar really is too good to be true, if you're trying
to make it with aluminum foil and a penny. There's a better way to do it, so in this
project, we're going to figure out exactly how to get this plate to make some noise.
The idea of making a speaker out of a paper plate is intriguing, and to do it for under
a buck is even better. But first, we have to understand how a speaker works. I've still
got these 8 Ohm speakers from a TV I salvaged in a previous video, and I'll sacrifice this
one in the name of discovery. I'll use a utility knife to cut the cone away from the surround,
exposing the basket, as well as this yellow diaphragm known as a spider. I'll cut through
that and snip these 2 wires, and am impressed at how simple a speaker really is. The bottom
of the basket is attached to a strong ceramic magnet, with a hole just big enough to allow
this voice coil to vibrate in. Ok we've got the basics, now let's see if we can make one.
We can use a foam bowl for the basket, an 8.5" paper plate for the speaker cone, 6 button
magnets, and a piece of printer paper to form the voice coil. This brings our pro-rated
cost to about $0.80 for this soon to be speaker. But what about insulated copper wire? That
can be expensive, and where do we get it? Well, almost anything electronic will have
some, you just have to know where to look. I know there's some inside this old TV, but
I don't have a sledge hammer to bust it open, so I'm gonna have to get creative.
Ok, I'm down to the circuit boards, and there's the piece I'm after. A small audio transformer.
These things are packed tight with the perfect wire for this project. I'll use my pipe wrench
pliers to rip that off the board, then use my bench vise to crack the ceramic casing
off. I'll peel off the insulating tape, and voila, we've got ourselves a nice roll of
insulated copper wire .. for free! Ok, we're ready to start building, so let's make the
voice coil first. Start by cutting a few strips of paper and rolling them around the stack
of magnets. Once we have a couple layers taped in place we can use a hot glue stick to help
unravel some wire. I'll wrap the wire about 50 times and then use some hot glue to keep
it in place. When that's cooled, we can pull the magnets and the inside layers of paper
out, leaving just this shell. The voice coil is done, but it's too long, so let's snip
it to size, and then hot glue it to the bottom side of the paper plate. While that's drying
we can cut some holes in the sides of the bowl, to make it look more like a proper speaker
basket. The next step is to hot glue our magnet stack to the bottom, and slide the coil over
top to see how it fits. It moves freely because of the gap we made earlier, and it's looking
good, so now we can hot glue the plate to the bowl and hit it with a little spray paint
for aesthetics. When the paint dries, there's only 1 thing left to do, and that's remove
the coating from the ends of the wires, so I'll do that with a lighter. Ok, It's ready
for a test, so I'm hooking it up to my TV with some alligator clips, to see what happens.
Well there you go, our 80 cent speaker is working, and if "..a paper plate speaker for
less than a dollar really is … too good to be true.", then we can call this part of
the myth UN-BUSTED. But it's not very loud. The magnets are cheap and weak, so let's try
something stronger. I've got a super strong 1" N48 Neodymium magnet I just got in the
mail. We can roll that up, and add some 26 gauge wire that came out of a sump pump motor,
and hot glue to secure it. The magnet and inner layers come out, and the paper gets
trimmed to size. Hot glue that to the plate, and glue the lead wires right about here.
This time let's use another plate as our base, and these markings are for some supports we'll
need to build. Those can be made out of a 3rd plate, just by trimming out the bottom
into a rectangle, folding them accordion style, and cutting into 2 pieces. I'm gluing them
to our base plate with the feet facing inward, and these will act as a type of shock absorber
for the speaker plate. Now we can add some glue to the tops, and join them to the plate
making sure the coil is overtop the magnet. A quick manual test, and it seems the suspension
on this is perfect. I'll burn the coating off the tips of the wires, and now it's time
to test this one out. I'm disconnecting the external speakers from my TV, and using these
alligator clips to connect the leads to our plate. I'm anxious to see how the paper plate
does with the stronger magnet.
That's pretty impressive. It's amazing to think that all
that sound is coming from this flimsy little plate, but it is. Just for fun, I'm gonna
pour in some water to see what happens.
And, that's probably the coolest thing I've seen
all day. Well that was a fun project. We UN-BUSTED a myth, and made a huge mess in the living
room. That's it for now. If you liked this project, perhaps you'll like some of my others.
Check them out at www.thekingofrandom.com