Upcycling Old Computer Speakers
by Philip Chien
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Upcycling is one step better than recycling - taking something no longer useful and turning it into something more useable. You help the environment and save yourself some money every time you reuse something that would otherwise be sent to a dump. It's better than recycling because recycling requires energy to collect the items and process them into fresh materials and it's rare for a high percentage of the materials in an item to be completely recycled.
Used powered computer speakers are extremely inexpensive. They're generally sold at yard sales and thrift stores for $5 or less, including their "wall-wart" power supplies. These speakers generally have permanent audio input cables with a 3.5 mm stereo (mini) plug which plugs into your computer's line out port (typically color coded lime green).
These aren't fantastic state-of-the-art speakers you'd want to use for a high end home theater system, but they're decent, and certainly worth the price. Occasionally I'll come across computer speakers with a subwoofer (a large speaker designed to replicate bass sounds) very inexpensively too. They're called 2.1 (pronounced two dot one) because they have two main speakers plus one subwoofer.
There are many ways computers speakers can be reused - add stereo speakers to a DVD player, inexpensive amplified speakers for an MP3 player, a high quality speakerphone for your cell phone, and to add surround speakers to your computer to name just a few possibilities. Basically any piece of electronics with a standard 3.5 mm (mini) audio output jack can be used.
You can use a pair of speakers and an inexpensive adapter cable to upgrade your home video setup from mono to stereo.
Almost all DVD players, Blu-Ray players, and stereo VCRs have a trio of color-coded output jacks. They're typically colored yellow, white, and red and correspond to Video, Left audio, and Right audio. The good news is different hardware and cable manufacturers all use the same color coding scheme. (It was much more challenging to hook up early VCRs and audio equipment before color coded standards became popular.) Red is also used on red/green/blue colored cables for component cable setups and yellow is also often used for digital audio (SPDIF) so you've got to be careful not to confuse them. Other than that all you have to do is match colors to avoid confusion when hooking up cables.
An inexpensive Y-adapter cable with white and red RCA plugs on one side and a female 3.5 mm stereo plug on the other end is all you need to hook up most computer speakers to your DVD or Blu-Ray player or stereo VCR.
Some mini stereo plugs and jacks are color coded lime green, but this isn't always the case. In most cases, including most adapter cables, the 3.5 mm plug is the same color as the cable (beige, black, and white are common).
In a typical setup your TV set is hooked up to the DVD player with either a direct cable from the DVD's video out to the TV's video in jack or through an R-F modulator to the television's antenna jack. If a mono TV has input jacks they will be color coded yellow (video) and audio (white).
If the red and white audio out jacks on your DVD player are not in use then hook up the Y-adapter cable and plug in the speakers. Presto, you've got the equivalent of a stereo TV and added a new dimension of experience to your DVD watching enjoyment.
If you've already got an audio cable hooked up from the DVD player to the TV set you've got a couple of choices. You can disconnect the audio cable from the DVD player to the TV and hook up your computer speakers (no sound will come out of the TV's speaker), or use a splitter so the mono audio still goes to the TV while the stereo audio goes to the speakers. An inexpensive RCA Male to two RCA Females splitter will do the job. (An adapter changes one type of connector to another while a splitter takes a signal and splits it into two identical signals.)
My preference is to use the splitter because it gives extra flexibility. If I'm just watching an ordinary DVD then I'll just use the TV's built-in speakers and leave the speakers unpowered. But if it's an action movie with lots of audio effects or a musical I'll turn on the external speakers.
This photo shows a gray colored splitter cable plugged into the DVD player's white (left/mono) audio jack. The white cable from the adapter is plugged into the splitter and the red cable on the adapter is plugged into the red audio output jack. The speakers are connected to the other end of the adapter. The other half of the splitter sends the left audio channel to the television, along with the existing yellow (video) signal.
Hooking up external speakers to your DVD player has an added bonus; the DVD player can also be used as an audio CD player. Just leave the TV set powered off. Put an audio CD into your DVD player and you can listen to CDs through the stereo speakers.
Another use for computer speakers is amplified speakers for an MP3 player. Just plug the speakers into your MP3 player and you're ready to listen to music without headphones.
My cell phone has a 3.5 mm audio jack. When it's plugged into speakers it can be used as a speaker phone or listen to a podcast. The phone's built-in anti-echo circuit does a great job of eliminating feedback. If your cell phone doesn't have a mini jack you can probably obtain an adapter cable.
Many high end computer sound circuits have the capability to hook up extra speakers for a surround sound setup. In some cases the jack is marked "Rear/Line In" or just "Line In" and that jack serves dual purposes. Depending on how your sound circuit is configured the jack can either take audio into your computer (Line In) or send out audio to a pair of rear speakers. In other cases there's a separate jack marked "Rear", and possibly an additional jacks for Center/subwoofer and side speakers for a 5.1 or 7.1 audio setup. Check your sound card's documentation for details.
This figure shows the jacks on my ASUS motherboard (unless you've got a similar motherboard the jacks will probably have a different arrangement). Jacks 5, 6, 14 are the standard line in (light blue), line out (lime green), and mike (pink) jacks. Jacks 3, 4, and 15 correspond to the side, center/subwoofer, and rear speaker jacks. Since this motherboard also has digital audio outputs (17 and 18) it can hook up directly to a home theater system.
Another approach is to upcycle an old cassette boom box. Cassettes are mostly obsolete and there are plenty of working used cassette players available for almost nothing. I recently picked up a portable karaoke cassette player for $1 at a yard sale. The seller apologized that the microphone wasn't working anymore, so it would only play cassettes, but that was fine by me.
In theory you can disassemble the boom box and solder wires directly to the circuit board's audio inputs, but there's a far simpler solution - a car cassette adapter. These handy devices were originally designed so cars with cassette players but without built-in CD players could use a portable CD player. Now they're marketed primarily to hook up an MP3 player to a car's stereo system. They work fine for non-auto applications and you can pick up used ones at yard sales and thrift shops for about $1.
The main difference between car cassette players and most boom boxes is the orientation of how the cassette is inserted. In cars they're inserted sideways (small side) while in most boom boxes they're inserted flat, either on the top or front.
With a car stereo the adapter's cable comes out of the front of the unit. It's slightly trickier with a boom box since there's no opening for the cable. In most cases you can just squeeze the cable through the opening without any problems. In others you may have to notch a hole in an appropriate place for the cable to pass through.
Cassette adapters must be inserted right side up. As a normal rule it's the side with the label.
All you have to do is press play on the cassette player and you've got an amplified speaker.
I pick up used speakers at yard sales whenever they're inexpensive enough because they are so versatile. I've paired them with MP3 players as presents, helped friends upgrade their DVD setups to stereo, and set up one unit in a laboratory so anybody could hook up an MP3 player if they wanted background music while they worked.
photos copyright 2012 Philip Chien. All Rights Reserved.
Order a RCA 2/Female to 1/Male Y Splitter Cable (6 Inch, Gray) from Amazon.com.
Order a Gold Plated 3.5mm Stereo Female to 2 RCA Male Y-Cable - 6 Inch from Amazon.com.
Order a Maxell CD-330 CD-to-Cassette Audio Adapter from Amazon.com.
About the author
Philip Chien has been working with electronics for most of his life.