Laptop Speaker wiring help

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Hi Guys,
I'm new to these forums and am a real noob.
I am making an Altoids tin speaker system and pulled some speakers out of an old Dell laptop.
The speakers are rated 4 ohm and 2 watt.
They have 4 cables- 1 red,2 black and one white.
Can someone help me in wiring these to a 3.5 mm jack and power supply.
Also is some kind of amp required for them.
I will post a picture if required.

Thanks in advance.
 
There's T-amp boards at eBay for under $10 shipped. Search for TA2024. It's too big to fit in an Altoids tin, and has too much power, unless you use some restraint with the volume knob. Highly recommended if you are building a larger portable system.

A search for "amplifier board" turned up a bunch of 3W stereo amps for under $5 on eBay. Probably all using the PAM8403 chip which can run from 5V (so you can power it from USB). Some include a volume control, and they're tiny enough to fit in an Altoids tin. Datasheet here: http://www.poweranalog.com/pdf/PAM8403.pdf That's at least 10 times as much power output as an LM386.

Stereo amps can sometimes be stripped from abandoned CRT TVs. It's usually a big chip with pins along one edge and a heat sink on the other, near where the speaker wires plug in. With some luck you can find both the chip datasheet and the TV schematic online, like I did with a Sony TV.
 
On the face of it, it should work. But I'm skeptical as to how it can possibly achieve that power into 8 ohms. See the discussion here: http://www.diyaudio.com/forums/class-d/192967-tiny-pam8610-10w-10w-board-problems.html Maybe an amp based on the Y148 chip is better; I found one on eBay for about $14, but you can get them from Dealextreme for under $10 including shipping. I ordered one for myself just now. It is physically larger, though, so may not fit in your Altoids tin.
http://www.diyaudio.com/forums/class-d/202411-y148-amp-module.html
Y148 Audio Amplifier Module - Free Shipping - DealExtreme

You could give the first amp you mentioned a try; it'll run from 5V, is very small, and won't overpower your speakers. A Y148, TA2020, TA2024 amp would need 12V and a larger case, but could deliver room-filling sound with the right speakers. 10 watts RMS or so is the same as "high power" car head units actually deliver, and that's enough power for bass you can feel (in a very small room like the inside of a car, anyway).

If you're salvaging from a dead laptop, there may be a suitable amp chip on the board already. Figure out where the speaker leads and traces end up.
 
Thanks Dangus,
I really appreciate your help. I was looking on dealextreme and found one of these. VMA2016 2*10W Audio Amplifier Module - Free Shipping - DealExtreme
It looks small and I think would be suitable.
If this works could you please tell me how to wire it. I will post some pictures of my speakers if needed.
If I can't make anything to fit into an altoids tin, I will step up and make a boombox that can fill a very large area (at least an area of 1000sq ft.) Could you tell me if this is possible for less than $100.
 
It certainly is very small, but I don't know anything about it. I guess you could wire directly from the module to jacks and speakers.
They are discussed here: http://www.diyaudio.com/forums/class-d/172143-simple-little-class-d-modules-v-module-vma2015.html

If you want tiny, then a module that runs from 5V is the way to go. If not so tiny, then the Yamaha seems like a good choice. How loud it gets will depend mostly on the choice of speakers. It's often possible to find really nice small bookshelf speakers at thrift stores or yard sales for the price of a McDonalds meal. Likewise, car speakers. You may be able to get OEM pulls from car stereo shops for nothing.
 
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