Instructables

Old Stereo headset found, but it has an odd array of solder points and i can't seem to get any sound, any ideas?

Hi there! I recently found two old sony headphone speakers, but i can't seem to get any sound out of them. It's a standard L/R speaker set that was enclosed into each ear piece. The odd thing is though that there are 8 solder points on the speaker pieces. One which is black blobbed and two that are white blobbed (i'm assuming it's to prevent shorts). Two wires are connected to two of the solder points (they don't seem insulated though...) I've tried various connection methods to make them produce any kind of sound, but nothing happens. I'm assuming they still work because they look intact, but...well any ideas? I don't have any expertice with audio equipment, but i do have basic electronics experience... I know it's kind of an odd question, but i'd really like to use these speakers and i wanted to make sure i wasn't doing anything wrong. Basically i've been trying to connect various music players to a mini jack port using a microphone mini jack cable (seems to work for all other purposes) and then tried to connect the speaker wires to the jack port solder points (in various ways).
I'm probably going to feel really stupid as the answer is probably really simple x3 I hope it makes sense!

i should probably specify that the main problem is that i can't get any audio output from them, aka. they're silent no matter what i hook them up to


Picture of Old Stereo headset found, but it has an odd array of solder points and i can't seem to get any sound, any ideas?
6 Ohms? Car subwoofers with dual voice coils require an input from the amplifier to both coils. In other words, 4 connectors in one speaker. I doubt this little speaker has 3 voice coils though... (i see 6 solder points)
Eirinn (author)  taylorinalaska5 years ago
Thank you for the reply.
Some of the solder points are covered by black goo and some by white goo - the quality of the picture isn't very good...I'm pretty sure that there are solder points under them so it's around 8 solder points... Would this tiny speaker really need an amplifier circuit? I'm very new to electronics and especially audio equipment so i'm not sure what you mean with 6ohms in reference to a speaker, voice coils an so on. But thank you for the reply in any case it gives me a few more words to look up and toy with . i could use some more help though..
IMO, amplifiers are the most fun thing to work with. Every speaker needs an amplifier, and every ipod, stereo, car head unit, et cetera, has a built in amplifier. In other words, they would need an amplifier, but not a 800W car amplifier like people think of. Usually ~ <1W. Learning about car audio helps alot, and building amplifiers is the best way. I would reccomend those beginner electronics kits at radioshack, i bought one, used all the parts, and dissasembled te actual board for parts. I'm glad to see you've taken an interest in electronics, theres nothing you can't do once you learn.
Eirinn (author)  taylorinalaska5 years ago
I'm learning more and more slowly...i'm still building tiny circuits that makes a light blink or a motor turn, but it has interesting side effects. I can more easily discern hardware problems in computers, avoid overcharing lighting components and soon i'll have a new desk lamp powered by low power LEDs <3 The problem is, i should probably edit the question so it makes more sense, that the speakers wont give out any sound at all. The resistors/impedance and the amplifiers makes for awesome modding as the next step. But without me getting any sound out of them... It's quite odd though, i'm not used to speakers breaking down and they look intact - the magnets aren't demagnetized and the speakers look in pristine condition. I know it could be anything, but...well i thought i'd ask. Thank you for your help so far!
Ask/try/look at these things... What did you hook it up too? What size are the speakers, any specs on them? (wattage, Ohms, etc) What about the other speaker? Does it work? What type of jack were the headphones originally on? Did they work before the disassembly? What was the original jack soldered to? (which contacts) Have you tried reassembling it back to how you found it, or back to its original state? Parts of the speaker may have just corroded, such as glue, rubber, and so on...
Eirinn (author)  taylorinalaska5 years ago
I forgot to add that the sound i get out of the speaker is very quiet.... af 100% (normal) power form the nDS i get a quiet music signal from the headphones.. so my guess is that it needs an amp.
Eirinn (author)  taylorinalaska5 years ago
The speaker has 919 printed on it in blue and has a red dot painted on the magnet and a red dot painted on the base, also a little hole in the baseplate (see picture). I tried disconnecting one of the speakers from my 5.1 surround set and connect them to the solder points (gently pressing no soldering) and i finally got some sound out of it. It seemed that the flimsy wires didn't connect well enough on my initial test to produce any kind of sound. I should be able to replace the wires with any kind of standard small electronics wire right? What i think is odd is that the audio wires are together inside a very thick rubber insulation, but the wires themselves don't seem insulated.. It looks like different colored copper wires with some sort of..plastic fiber or something so i figured i'd ask about replacing them (for different reasons). What i'm going to do is that i'm going to make a wrist gauntlet (sci/fi predator style) with an embedded nDS, a pair of stereo speakers and other kinds of goodies. I'll post an instructable if i manage to do it! I found a few old CD cases and i desoldered the volume wheel, if i build an amplifier circuit would i be able to use the wheel with it to control the speaker volume? In any case i believe my question has been answered so i'll mark it as so. But i could use some help regardin stuff like amplification and other things if you want to help. In that case i think PMs are better as to keep this clean. Special thanks to sound91 for the explanation of impedance btw!
Eirinn (author)  Eirinn5 years ago
I forgot to say that these speakers are around 4cm in diameter so i was really surprised about the large amount of solder points...(which are on a tiny pcb attach to the speaker...).
mattccc5 years ago
the voice coil may be dead
sound915 years ago
The 6 ohms means six ohms of impedance. Here is an example of how impedance works. Imagine you have two speakers, speaker A has 6 ohms of impedance and speaker B has 12 ohms of impedance. If your volume control is left at the same level, Speaker A will be louder than speaker B because it has a lower impedance. Higher quality speakers are usually made with higher impedance. In my experience, there should only be two wires on each speaker. The ground and signal. 6 ohms isn't very much, so you could hook a mp3 player or CD player directly to it and still get plenty of volume. I have a small speaker with 6 ohms of impedance, and I use my i-pod with it when I don't need music very loud. Good luck.
Eirinn (author)  sound915 years ago
That makes sense regarding the audio output once i can get sound out of it, thank you :D