LED VU meter that dances to computer music

Step 2: Build the circuit and connect the sound source

So I followed this schematic when I build the circuit. I used a 6V source (4AA).

Pin 5 may get a little confusing. What happens there is pin 5 goes to node "A". Node "A" attaches to a resistor (1M) which goes to ground. Node "A" also connects to the negative of the capacitor.

Other than that it is straight forwards. The negatives of the LEDs face the chip. The positive ends of the LEDs are connected to the source.

The Input. Now this is porbably the most important step. The input comes from sound card on my computer (to be able to listen and view this effect you need to get this: http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10218&cs_id=1021802&p_id=667&seq=1&format=2&style=

The male end of the above goes to the sound card where you speakers are now. One female end is connected to the speakers you just unplugged. The other end will be this:
http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10218&cs_id=1021802&p_id=644&seq=1&format=2&style=

You take 1 end of this and cut it and split the wire to look like the picture shown.

Comments

[Wally_Z]

This does not work. I have tried this with 6v and 12v as a power source. I hooked this up exactly the way you have it. I still can't get it to work.

[spasha]

if any other ic is there like LM3915 because in india bangalore this ic not available please help me.

[pjahster]

3 things: 1. So I should just leave the white wire alone? It's not needed? 2. The cable shown is the M/M cable? 3. The 2 stereo jack cable isn't altered in any way, right? I am thinking of doing this for a school project, so any help would be appreciated.

[Ben The Builder]

I don't know about the other 2 but for #1 you do only need the two he has, I think the uncoated one is the negative and you need either the red OR the white, one goes to the left ear the other goes to the right ear but if you want separate VU meters for each ear double out the negative and run this with the red and the negative and the white with the negative