I’ve been on a bit of a laser kick lately. I was searching through YouTube and came across Dr. Altman’s “Amazing Laser Music Can” which I thought was a very impressive effect for very little money. I had a spare Sunday afternoon, and decided to make one for myself. If you’re the impatient type, here’s what the final product produces, not too shabby:
Parts
I started off at the local dollar store, which amazingly enough had everything I needed for about five dollars.
- Three laser pointers, $3. This personally boggles my mind – an electronic device, relying on the most advanced theories of physics humans have developed, the absolute cutting edge of research less than 60 years ago, now sells for 99 cents. You don’t need to use precisely three, but you’ll probably want at least one. Or else bitter disappointment awaits, because you need a laser for a laser light show.
- A package of ballons, $1.
- A small mirror, $1.
I also had a few things around the house.
- A can.
- Duct tape.
- Zip ties.
- Clothes pins.
- Popsicle sticks.
If you need to buy them don’t worry, you won’t blow your budget. Plus, once you have an excess amount of duct tape and zip ties you’ll wonder how you ever lived without them.
Concept
What we’re trying to do is mount a laser so that the beam bounces off a mirror attached to a membrane (aka balloon) stretched across the mouth of the tube. When the membrane vibrates, the path of the laser will be changed in a semi-periodic manner, leading to (hopefully) beautiful patterns that sync up to sound.
Mounting the Lasers
You can do this with one laser, but since the lasers were so cheap I picked up a few. The first thing we need to do is zip tie (or glue, or whatever) one side of the clothes pin to the popsicle stick. This will create a nice little angled place for the laser to mount to.
Then, we need to attach the laser. Another zip tie does well for this, really crank it down to make sure that it isn’t going anywhere. Finally, we need to create some sort of method to ensure the laser remains on for an extended period of time without us having to hold down the little button by hand. Zip ties to the rescue again! Just position it on top of the button, and slowly tighten it until the laser turns on. The zip tie should then be loose enough that you can move it back and forth to turn the laser on and off for as long as you like.
Dude that is cool. I am going to make some and position them around my drum kit.
JT
Hats off to that idea! I’m so there.
Hi Geoff,
Reddit, my source of interesting stuff, introduced me to your pages on gasoline and now lasers. Your reference to the Royal Military College made me wonder if you are related to Cec.
Stan
Hey Geoff,
This is very cool, and I see you are at RMC, I’m joining up next week as a NCM LCIS Tech, you might end up being my boss!
What a brilliant idea! Thanks.
Wow man, I’m so there!
You can just put a small mirror onto the middle of the speaker directly with a little double-sided tape – point a laser at it and you get the same effect with even less hassle, used to do it as a kid.
It works really well if you attach the mirror to an old speaker and bounce the laser off
The best way to do this is like so:
Mount two mirrors at 45 degree angles on the center of two separate speaker cones (Mid range is best for overall detail). Now angle the two speakers/mirrors so the laser bounces off both. Make sure you run a mono signal through both of the speakers for it to look best.
You will find that this setup is far better, you will get a super responsive light show. Try using a synthesizer instead of the music you’re listening to and jam along. It’s really fun!! Me and my friends used to spend hours creating new and better designs with some really high-powered lasers (lasers that take up half the room with transformers and fill the room with static)!
What dollar store in Kingston sells laser pointers for $1?
I went to a dollar store in Ottawa and couldn’t find anything remotely close to a laser pointer…
blargle – I went to the one in the Kingston Center, across from the Loblaws. That’s the peril of those stores – often you can find thing you’d never expect, but don’t expect consistent inventory.
If you’re looking for cheap lasers and don’t mind the wait for shipping (they’re in Hong Kong but at least the shipping is free), DealExtreme is about as cheap as it gets.
Scientific American published a DIY laser show article in the 1980’s with info on building a 2-axis deflector with small speakers, a random distortion disk from gooping up a piece of clear glass or plastic with thick transparent adhesive and mounting it to a slow turning motor and fun with polarizing film and diffraction gratings. It detailed how to make your own diffraction gratings by laying out strips of black tape on a large sheet of paper then photographing it from a distance. The developed black and white negative worked like a polarizing filter.
Another trick for randomness was gluing plastic wrap over a woofer speaker then gluing a piece of mirror to the plastic wrap.
IIRC the same issue had an article on building a mercury vapor laser tube from scratch.