Sound Activated Leds diagram

[Rodent]

Here is a link where i got some of my Information
http://www.danielandrade.net/2005/12/06/howto-blinking-leds/

This can be used on
xbox 360,Wii,PS3s just solder the points to the av out put on the mother board where the Left and Right audio points are

Here is the diagram I used for my Flame Activated LED xbox 360 console

[Frosty]

great job rodie

[nabby]

I'd really like to put this in a PS2, and I've seen more variations on the internet on this circuit than I can count, but I've heard a bunch of electrical experts constantly complaining about how this is a poor design and will fry the transistors and won't last long, can overheat and damage the audio input, etc... I've heard there should be a protection diode in there somewhere and some sort of resistor on the line between the audio line and the transistor base. Have you gone back to your original design at all and tweaked it? How is this mod holding up for you after a few months of use?

[Rodent]

I'd really like to put this in a PS2, and I've seen more variations on the internet on this circuit than I can count, but I've heard a bunch of electrical experts constantly complaining about how this is a poor design and will fry the transistors and won't last long, can overheat and damage the audio input, etc... I've heard there should be a protection diode in there somewhere and some sort of resistor on the line between the audio line and the transistor base. Have you gone back to your original design at all and tweaked it? How is this mod holding up for you after a few months of use?

I havent had any issues with this it at all I had this in my xbox 360 console for well over a year never had any issues.

Even after selling the console and the buyer destroyed the console, he sent it back to me , still was working , just the case was damaged and some of the wiring had been pulled out, I resoldered the few wires and was still working .

Here is the results.
Rodent's XBOX 360 sound

[nabby]

Glad to hear it! And thanks for taking the time to reply. My buddy gave me a PS2 slim to work on because he had lent it to a friend for a few months and when he got it back,  it wasn't reading discs any more. I opened it up to find a large family of roaches had set up a home inside it. Having a nearly unlimited supply of circuit board wash at work, I took the whole thing apart and cleaned it up well. A replacement laser is on the way, and now he's talking about paying for any parts I need to really make it look nice. A translucent shell is on the way, and the sound-reactive LEDs sound like a great idea, I just got worried when I started hearing all the criticism. Only problem is I have had to tweak the design a little since the PS2 Slim only has an 8.5V power source. How many total LEDs did you use in that 360?

[Rodent]

Glad to hear it! And thanks for taking the time to reply. My buddy gave me a PS2 slim to work on because he had lent it to a friend for a few months and when he got it back,  it wasn't reading discs any more. I opened it up to find a large family of roaches had set up a home inside it. Having a nearly unlimited supply of circuit board wash at work, I took the whole thing apart and cleaned it up well. A replacement laser is on the way, and now he's talking about paying for any parts I need to really make it look nice. A translucent shell is on the way, and the sound-reactive LEDs sound like a great idea, I just got worried when I started hearing all the criticism. Only problem is I have had to tweak the design a little since the PS2 Slim only has an 8.5V power source. How many total LEDs did you use in that 360?

Shouldnt have to worry about tweaking the design if your powering it with 8.5 volts. It should be fine, just the resistors will be different for the leds you use.. I have made this with a 5 volt system and 3.3 volt system. you should be totally fine the dpdt switch is so you can turn it on all the time or turn it on so it pulses. I used 20 leds in the Flame case . I used only 4 leds in this plus the 4 rol leds in this mod , with almost the same set up..  powered by the 3volts off the controller its self and added 9volts to power the sound card.
Sound activated Led Controller by Rodent.mov

[nabby]

There's a guy I'm talking to over on a circuit building forum who insists that the "line level" we get from audio pin-outs on the mobo shouldn't have enough voltage to turn on the transistor... line level would be 150mV to 250mv RMS / .35V peak which isn't enough (it needs to be 1/10th of the full power to turn on), but headphone jacks can get up to 1.8V which is plenty, so now I'm stuck wondering why this mod works without an amplifier chip. Any idea what kind of voltage the a/v points put out?

[Rodent]

I think your making it more complicated then it is I showed you two different MODS I done with this set up and they work perfectly... Try it you will see for your self... I wouldn't of posted it .. if it didn't work.

[nabby]

Every day at my job, I see things that work that seem like they shouldn't. I find it intriguing. It's the strange differences between things that work on paper and things that work in real life, and I have a dirty habit of asking "why" to everything.

[Kool1zero]

There's a guy I'm talking to over on a circuit building forum who insists that the "line level" we get from audio pin-outs on the mobo shouldn't have enough voltage to turn on the transistor... line level would be 150mV to 250mv RMS / .35V peak which isn't enough (it needs to be 1/10th of the full power to turn on), but headphone jacks can get up to 1.8V which is plenty, so now I'm stuck wondering why this mod works without an amplifier chip. Any idea what kind of voltage the a/v points put out?

I have literally pages of notes of how and why transistors work. I've also got lot of formulas if you want them. The main thing to note is that the tip31 i a bipolar junction transistor (BJT) which is a current biased transistor not a voltage controlled one. the beta is always between roughly 100 and 150 for a circuit like this. the opposite would be a  field effect transistor (FET) its a voltage controlled device.

I'll grab my notes and formula sheets out and do a workup of the circuit and whatnot tomorow.

[nabby]

That's a lot of help. I read that and the lightbulb finally came on. I totally see why this works now.



I've been doing a lot of studying... it seems all BJT transistors, while current driven, have to have an input voltage of 0.6V at the base leg before they start functioning. It's their flaw, if you will. I'm guessing these game consoles are running 2V peak to peak, so anywhere between about half and full voltage through the sound lines is enough to turn on the transistor and at that point it's running on current.

 The other neat thing I've discovered is if you add a large ohm resistor (100K seems to be good) between where your audio + line connects to the transistor, and connect the other end to ground, whenever the audio is supplying voltage, it takes the path of least resistance and goes through the transistor, but when the audio switches to off, the residual current in the transistor goes through the resistor to the ground. The result is that it makes your LEDs turn off even quicker.