Sound Activated LED Circuit?

[Dc5e]

Does anybody know how I can make a Sound Activated LED Circuit?? I want to hook up some LED's and make them light up based on whats coming out of the computer. So if i'm playing techno music, the LED's would blink with the beat/music.

And also, what kind of circuit design programs are out there that i could possibly grab?

And one more thing, whats the difference between DPST and SPST switches??

 

[nettron1000]

You could try using the output from your computer speakers to drive a circuit designed around a dot/bar graph LED display driver IC such as a LM3914 or 3916. Most computer speakers have a headphone jack output that could be used as the input to the driver circuit.
If you mean to drive a circuit directly from your computer , you will first need a digital to analog converter (DAC) IC and a amp circuit to up the wattage.

And also, what kind of circuit design programs are out there that i could possibly grab?

Do you mean a schematic drawing program? This question as bin asked a few times on this forum and as bin well answered, check the archived posts.

whats the difference between DPST and SPST switches??

The letter "D".....heheh just kidding.

A SPST (single pole single throw) switch is just a simple on-off switch with one contact point that can be opened or closed. A DPST (double pole single throw) switch has two contact points that are seperate from each other, sorta like two SPST switches combined.