How to Make a Portable Mp3 Amp From Old Computer Speakers
Intro: How to Make a Portable Mp3 Amp From Old Computer Speakers
have you got a pair of old computer speakers lying around that you dont need?
want to make a decent iPod/mp3 amp?
these speakers are powered via a PP3 9V battery
materials:
speakers
snap on clip for 9V batter
9V battery
audio source
tools:
soldering iron and solder
screw driver
wire cutters/teeth
wire stippers/teeth
want to make a decent iPod/mp3 amp?
these speakers are powered via a PP3 9V battery
materials:
speakers
snap on clip for 9V batter
9V battery
audio source
tools:
soldering iron and solder
screw driver
wire cutters/teeth
wire stippers/teeth
STEP 1: Disassemble Speakers
your speakers might not be 9V, if there not you could possibly use AA batteries in series in aholder or use a gel cell, bit heavy though.
disassemble the speaker with volume and power input, unscrew it from the back, there should be a transformer attached to the back, this is what takes the 230V (110V) down to 9V or the working voltage for your speakers.
on the transformer it should say the primary and secondary voltage, the secondary voltage should be lower, 9V hopefully, if it is not 9V you may still be in luck, if it is 3V use two AA batteries, if its 6V use 4, if its 12V use either 8 AA batteries or a car battery or gel cell battery, look online for one.
however, if you want, you can put a batter inside if you have room, or outside if you dont, and put the speaker cases back together.
disassemble the speaker with volume and power input, unscrew it from the back, there should be a transformer attached to the back, this is what takes the 230V (110V) down to 9V or the working voltage for your speakers.
on the transformer it should say the primary and secondary voltage, the secondary voltage should be lower, 9V hopefully, if it is not 9V you may still be in luck, if it is 3V use two AA batteries, if its 6V use 4, if its 12V use either 8 AA batteries or a car battery or gel cell battery, look online for one.
however, if you want, you can put a batter inside if you have room, or outside if you dont, and put the speaker cases back together.
STEP 2: Removing Board, Speakers, and Wires
now you need to remove the board and speakers from the two speakers. to remove the speakers there should be screws holding the speaker in at the corners. for the board there is likely to be screws holding it into the case, and the potentiometers will probably have nuts holding them on. so pull the knob off the front of the volume control and the nut should be exposed. use needle nose pliers or similar to remove it, then repeat for any other control knobs.
STEP 3: Adding Power Connector and Removing Second Speaker
in this step we will remove the speaker from the second speaker case, and also add the power connector.
for these speakers to be powered from a 9V battery or whatever battery is used you need to add the connector, if you are using a 9V battery, use a PP3 battery clip, you can either solder it directly onto the board or you can cut the wires from the transformer and add it there, this will give you more cable length, and mean you wont have to desolder and solder onto the board.
if going for the second method strip both wires (teeth or wire strippers) then add the connector and twist the wires together and apply some solder.
if you want you can test it now, plug the input jack into your audio source, mp3 player etc.
if you hear music, well done! if not, not so well done, check cables, and battery life.
if all goes well, time to remove the second speaker, unscrew the case and then unscrew the speaker from the casing. now you will have to either cut the cable from the speaker to the board or melt the solder off, thread it though the hole in the back of the case, then resolder, i went for the first option, but as the cable broke off the speaker later i ended up doing the later option but slower.
for these speakers to be powered from a 9V battery or whatever battery is used you need to add the connector, if you are using a 9V battery, use a PP3 battery clip, you can either solder it directly onto the board or you can cut the wires from the transformer and add it there, this will give you more cable length, and mean you wont have to desolder and solder onto the board.
if going for the second method strip both wires (teeth or wire strippers) then add the connector and twist the wires together and apply some solder.
if you want you can test it now, plug the input jack into your audio source, mp3 player etc.
if you hear music, well done! if not, not so well done, check cables, and battery life.
if all goes well, time to remove the second speaker, unscrew the case and then unscrew the speaker from the casing. now you will have to either cut the cable from the speaker to the board or melt the solder off, thread it though the hole in the back of the case, then resolder, i went for the first option, but as the cable broke off the speaker later i ended up doing the later option but slower.
STEP 4: Finishing Up
now you should have finished, all you have left to do if but the board and speakers in a suitable housing or put it back in the old housing, i was planning on mounting the speakers inside my bag with holes cut for sound to escape, but thats for another instrucable
hope it all works! have fun sharing your music tastes to the public!!!
hope it all works! have fun sharing your music tastes to the public!!!
29 Comments
Adammm124 8 years ago
I did get sound.. But it was very quiet. Not the real volume of the speakers. What's up with that? I tried to check the voltage with a multimeter and it acted like it was shorting out. Maybe one of my solders was cold since it was hard to solder on to the circuit board.
searly2 10 years ago
LazyH 9 years ago
A simple nine volt battery would be the simplest solution, but 6 AA C or D cell batteries would last a lot longer. To an extent, the lower voltage will only slightly lower the clipping amplitude (max volume) of the amplifier circuit. I tested the amplifier circuit in a set of sony speakers I had and the voltage was originally 12 volts, but I could get to as low as 8 volts before the sound was distorted during louder sections of music when played at normal listening levels.
omendoza2 10 years ago
Encik_Google 11 years ago
Tv1996 14 years ago
K'nexFanatiFreek 12 years ago
here's a video that explains in inductors: http://www.youtube.com/watch?v=STDlCdZnIsw
FriedRiceFreak 13 years ago
K'nexFanatiFreek 12 years ago
jwarburton1 12 years ago
Blubber300 12 years ago
CDAWWGG 13 years ago
liamhickey 15 years ago
tomtortoise 13 years ago
Whales 13 years ago
Valgarn 14 years ago
odavidson 14 years ago
With mine a freshly charged 9V battery lasted me about 5 hours, at about 1/4-1/2 volume. It depends on your speakers but in normal use they shouldn't draw much current.
Valgarn 14 years ago
won't you drain the 9v battery like, veeeery fast?
my transformer says: O/P:9V-1A
It's working perfectly though, sound quality is as good as with 230v from the wall^^
magnam 14 years ago
and i connected 9volt battery as power source, and i conect headphones to headphone jack.
it works, but audio quality is very poor. can you tell me what might be the reason?
my speakers are old so maybe its somthing wrong with my board???
hlp pls.
deathnote_213 14 years ago
but i'm serious hehe.....great thinking keep it up....