Instructables
Picture of Computer Speaker Conversion
Sick of having to cart a pair of computer speakers around if you want to hear some tunes away from you computer? Me too. In my room the only speakers I have are a pair of computer speakers which are stuck to my desk because of cords that loop around the back of the desk. If I wanted to use anything other than earphones away from my desk I wasn't easily able to because of the difficulty of moving around the computer speakers. This prompted me to get a pair of old computer speakers and put them inside a single box so that there were a minimal amount of cords and so they'd be easy to relocate when I needed to use them somewhere else. This instructable will guide you through this process of repurposing 2 computer speakers into a single unit. By the way this is my first Instructable so all comments and criticisms are greatly appreciated!

What you'll need:
- Pair of old computer speakers
- Soldering iron and solder
- Screwdriver
- Something to put the new speakers into
- Sidecutters
- Tinsnips (only if you want to get the old speakers apart without having to cut and resolder wires)
- Power drill, with drill bits and hole saws.
- Some way of decorating your speaker enclosure (not necessary, but something like an airbrush or normal paints are a good way to go).
- A way of fixing parts of your speakers to their enclosure. Screws, hot glue or Silastic are best.

Oh and a disclaimer, be careful. If your speakers have a transformer like mine you will be working very close to a lot of power. So whenever your doing anything to your speakers, make sure they are unplugged. I'm not responsible if you blow yourself up.
 
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nivekrome3 years ago
Ok so I've built this instructable. Tested my speakers after disassembling the original casing. Did some offboard rewiring of my pots/volume, bass, and treble. Built a clock and a lamp. And retro fit it all into an old am radio. Basically Ive put alot of work into this. Now I placed my amp assembly and speakers in and BOOM no sound from one speaker!? I've checked my connection and even tried other speakers? All end up the same, very very little sound. Anyone have any other suggestions?? Its the speaker directly connected to the pcb if that helps? Really wanna get this working
can we use electric tape
NO!! just kidding I dont see why not...
radiorahim5 years ago
What's the best way to hook up some batteries to make it a boom box? I need it to be portable for my skating needs. It will probably have a switch to switch the power input from AC to DC. Thanks.
Since the cabinet is made of thin plastic (in this case), there will be a wide range of frequency ranges comming out 180 degrees out of phase anyway. If you're going to concern yourself with a tuned port, insulate the inside of the tub with some acceptable substance (fiberglass or similar).
drcrash7 years ago
If you're going to take speakers out of a well-designed enclosure and put them in a new enclosure, it's a good idea to understand a couple of things about enclosure design and copy those aspects of the original enclosure. Most speaker enclosures are bass reflex enclosures tuned to the characteristics of the driver. In particular, the VOLUME of the box is important---your box should be the same size, even if it's a different shape. (Shape doesn't matter as much as the volume of the box.) It should also have a hole in the front of roughly a certain size. The box and the hole act as a filter, by delaying the pressure wave coming off the back of the speaker and redirecting it to the front. The pressure from the back of the speaker is the reverse of the pressure from the front, and there's a slight delay in that sound path, because the pressure has to travel a little further to get to the listener. That delay is important. If the enclosure is designed right, the sound coming out of the hole will be in phase with frequencies you want to reinforce, and out of phase with frequencies you want to partly cancel out. In particular, most drivers have a peak in the bass response, and steep fall-off at frequencies below that. You engineer the delay to partly cancel out that peak (by being 180 degrees out of phase) and reinforce frequencies about a half an octave above and below that. That smooths out the bass response and extends it about a half an octave lower. (IIRC. It's been a long time.) You don't really need to understand this to replace a speaker enclosure with one that sounds pretty good, too. You just have to know that the volume of the enclosure and the size of the hole matter, and copy them. The shape of the enclosure doesn't usually matter nearly as much, so you have a lot of freedom to substitute more convenient or cool-looking enclosures. Just make sure your enclosure has the same volume and a similar-sized hole in it. If you choose the wrong size of box, you may do a lot of harm to the sound. It may reinforce frequencies that are already too loud, and cancel out frequencies that are already too quiet. (If the hole is too small, it won't do much good in terms of shaping the bass response, and will "whistle"---air pumping through the little hole will generate extraneous noise at higher frequencies.)
Only thing is drcrash, the mathematics to tune a speaker enclosure to a specific frequency are very complicated and without the proper datasheet with the thiele-small parameters on, it is almost impossible to calculate how long the port should be and how big. Basically what I am saying is that putting a port in a box that hasn't been calculated properly could make it sound worse rather than better. The best way for speakers such as these is to put them in a simple sealed enclosure that doesn't need any calculations for it to give a reasonably flat frequency response. After all, it is meant to be a simple project that is portable.
Computer speakers of the caliber used for this project are likely generic drivers placed in generic plastic enclosures by the original manufacturer anyway. While most of your observations are valid, it is doubtful that the manufacturer paid as much attention to detail. Problems of phase should be minimal and a moot point when drivers are in such close proximity (point source). Box volume without a port needs to go up and usually produces a more accurate, though less efficient and less dynamic, speaker. Were he to port it, there would have to be an appropriate tuning frequency of said port that corresponds to roughly that of the lowest frequency the driver is able to reproduce. That means a tube of a particular width and length. Done correctly, this would improve the overall sound quality of the speaker. At the end of the day he would, however, still have $2 drivers stuck inside of a Tupperware container and driven by a flea powered amplifier. IMHO he should be happy with his wicked cool looking and convenient little boom-box without regard to achieving audiophile nirvana (which is a myth anyway).
TheCrimsonBinome22 (author)  Bignerd1007 years ago
Although I do appreciate all this input from everyone, your correct in assuming that at the end of day, this is just an instructable about how to make a cool, small and practical boom box. Maybe later in life I'll chase after this audiophile nirvana, but at the moment such a dream is far beyond my grasp.
I'm not really talking about audiophile Nirvana. Most of my speakers come from the Goodwill outlet store, for a few bucks. Some computer speakers really are better than the ultra-cheap, ultra-low-powered computer speakers, and cost less there. (I have a 200-watt THX-certified Klipsch sub-sat set, and there's a lot of stuff well below that but still above the cheapest generic drivers in generic boxes.) To me, it's worth starting with decent speakers if you're going to put the effort into a case mod. Audio quality isn't an all-or-nothing proposition. But then, maybe that's just me. If people just want an easy hack for the cheapest speakers, that's fine by me, too. Go for it. Nice instructible.
dude, although you are right about what you are saying, box volume, airflow etc... im sure people who are making this arent going to use this is a hi-fi needed sound enviroment, meaning they dont care much about their audio quality for their ipod/ mp3 player. Also, since when were COMPUTER SPEAKERS high quality. I have made something similar and you can barely hear the audio quality difference, no matter how bad you make the new box, either completly closed up with no airflow holes or no sides to the boxes. it doesnt make that much of a differnece.
HamO drcrash7 years ago
You failed to mention the two speakers in one enclosure. Frequencies canceling out because they will be out of phase from one speaker to the other. Of course with such a flexible enclosure this is all moot anyway.
brodyf HamO7 years ago
You could always just make sure to wire them in phase. Thaat seems to make the most sense to me.
HamO brodyf7 years ago
It's not the electrical phase that is the problem, it's the acoustical phase that would cause a problem.
brodyf HamO7 years ago
if the electrical phase is in sync, why wouldn't the acoustic phase be? That may be a dumb question, but I am somewhat new to audio electronics.
HamO brodyf7 years ago
If it's stereo or anything that is 2 separate channels a signal might be out of phase.
girrrrrrr2 HamO7 years ago
cant you just put something in the middle of the two speakers so the preassure waves is blocked from each other...
TheCrimsonBinome22 (author)  drcrash7 years ago
Wow thanks for the humungous tip! I really appreciate and will be taking it into account for next time. I was aware that the old computer speakers were bass reflex and that ! should try to replicate it but I couldn't be bothered and wasn't sure how much difference it would make. Since this is only an experiment I'll be doing a more careful job next time and will recreate a similar size enclosure to the original out of wood so i can get the measurements right. Again thanks!
ledzep5676 years ago
this sounds awesome!(pun un-intended lol) im making this for my art teacher because she spent the whole period complaining because the school computer wouldnt play the songs on her ipod lol
camb007 years ago
I'm just wandering coz I like a electronic noob is the transformer and the amp are safe to touch when it has been un plugged
TheCrimsonBinome22 (author)  camb007 years ago
If it's unplugged from the wall the transformer and the rest of the amp should be relatively safe to touch. As far as I can remember there are no big capacitors on the board that will store a charge so you should be okay, just make sure it's unplugged!
my computer speakers are a surround sound system and i have five speakers hangin out so whatever i do its probably not going to be portable, hey 'drcrash' this is suppost to be portable, not high quality....
HamO7 years ago
Bravo on such a nice instructable. Well done. Thanks for sharing.
TheCrimsonBinome22 (author)  HamO7 years ago
Thank you :D
buZztiaan7 years ago
Nice one :)
TheCrimsonBinome22 (author)  buZztiaan7 years ago
Thanks!
sdallesasse7 years ago
At first glance I thought you bought / found an enclosure that was made for the speakers! It looks really good! You may want to use a labeling technique found on here, Instructables, instead of hand writing your volume, base and trebble. It involves using a lazer printer and scotch tape.
TheCrimsonBinome22 (author)  sdallesasse7 years ago
Thanks! That labelling technique sounds like good a idea. I'll probably use it next time.