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I bought some very small speakers, but I'm not sure how to solder or connect wires ...

Should I bend the 'butterfly wings' on the left side upwards and connect to both 'wings' (it states a + and - sign on each wing). Since the wings touch the copper color chassis I think it would give a shortcircuit without bending.

The green part is not conductive (checked with multimeter).... so I'm almost sure to just bend the wings up a bit and solder wire to it... but want to be sure (not to blow them) :-)

enter image description here

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  • \$\begingroup\$ Update: I soldered wires to it... they work. Too bad the (stranded) wires which I tried to glue together with solder fit very hardly in a breadboard ... it would be better to cut 4 jumper wires in half and solder them directly (lesson learnt). \$\endgroup\$ – Michel Keijzers May 21 '17 at 22:49
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It appears the green / silver object is of the same material as used in making a printed circuit board (PCB). Which is usually fiberglass with a copper film. If so it will not bend with out breaking.

Solder two speaker wires to the two silver parts of the PCB.

If you like, try measuring the resistance. It should not be a dead short, but it will be very close. The "8 ohm" printed on the back of many common speakers is an impedance as seen from the amplifier which is switching the current back and fourth many times per second. So it "sees" the impedance of the speaker differently than an ohm meter which is not switching the current back and fourth at all.

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  • \$\begingroup\$ Thanks for the reply ... I just checked, and it's indeed 7 ohm (with my cheap multimeter and cheap speakers it might be 1 off). \$\endgroup\$ – Michel Keijzers May 20 '17 at 13:57
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    \$\begingroup\$ I should add, unless there is something very unusual going on (which I doubt), the positive and negative symbols are used to indicate how the speakers are wound. It should make no difference if you are using 1 speaker. But if you are using 2 (such as with a stereo sound source) you will want both speakers to travel in the same direction at the same time. That is, to have the same phase. So for stereo you should connect both speakers in a similar fashion. \$\endgroup\$ – st2000 May 20 '17 at 14:08
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    \$\begingroup\$ @MichelKeijzers It's probably not off. You want pretty much as low DC resistance as possible on your 8 ohm speaker but an AC impedance of around 8 ohm at useful frequencies. 7 ohm for a cheapo speaker sounds normal. Probably more than you wanted to know but an hyper-crude way to find an efficient speaker is to measure the resistance like you did and choose the lowest. \$\endgroup\$ – winny May 20 '17 at 14:23
  • \$\begingroup\$ Thanks for all additional info ... actually these speakers are more for 'trying'... cannot expect much from ultra cheap speakers like this, but I'm learning electronics (as a side hobby). \$\endgroup\$ – Michel Keijzers May 20 '17 at 15:47
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The "butterfly wings" are contact pads on a PCB affixed to the speaker. Use standard surface wire soldering techniques to attach wires to it.

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You can just do a conductivity test with the multi-meter. Keep one probe on the copper and other on either terminals(+&-) ,see if you hear the beep sound or not. if there is no sound on both the case you can just solder the corresponding wires. if that is not the case you should cut off the parts that is touching and test again. Be careful that you don't break or cut the copper coils from the speaker(if you are planning to bend)and solder the correct wires to each terminals.

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  • \$\begingroup\$ I did and the 'copper' color parts give 0 ohm so that's good. Since the wires may touch the copper color part, it should not be any problem. Which is good, because my soldering technique is very minimal :-) \$\endgroup\$ – Michel Keijzers May 20 '17 at 15:49

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