77Views7Replies

Author Options:

Help with sound reactive LED Answered

Heyy there since i am new to this forum i might have made this question in the wrong section

So...i have built a sound reactive LED with a TIP31 transistor that it is powered by a 5.2 volt power supply and it works like a charm! You just plug it on the wall and plug the 3.5mm jack on your output and done!

But here is the problem...my laptop's sound card is to weak to power the LED properly so i attached it to my stereo system.It worked better but when i turned up the volume it kept glowing instead of flashing to the beat because the music was loud.My question is..should i use a resistor between the stereo output and the sound reactive LED so it will flash when the music is loud? If yes how many ohms?


(PS I am new to these stuff but i know the basics and know how to solder two wires.)
(PS No2 I have attached some pictures with the simple schematic and the whole project.)
(PS No3 Sorry for my English it's not my mother language.)
(PS No4 The uploader is not working for some weird reason so i am not able to upload the pictures)

Discussions

0
None
mpilchfamily

5 years ago

What circuit are you using?

Let me suggest this video for helping you out. It will help you understand how to make a good 'clap' circuit. The mic in the video example can be replaced with an audio jack to connect to any audio signal.

0
None
mpilchfamilympilchfamily

Reply 5 years ago

Also the video linked to at the end is something you may want to look at as well to take your project a bit further.

0
None
KickBustermpilchfamily

Reply 5 years ago

Τhank you very much, but i cant see the video...Here is the schematic of the circuit and as i said it is working very good at the volume about 15/32

Building-the-circuit1.jpg
0
None
mpilchfamilyKickBuster

Reply 5 years ago

Your not going to get any kind of control with that. You need to build a clap circuit using an opamp. It's a fairly simple and common circuit.

http://www.youtube.com/watch?v=y0Q0ERSP24A

0
None
mpilchfamilyKickBuster

Reply 5 years ago

Yes it works. But it's only able to register when there is a big enough hit in the audio. As you noted if you turn the volume up too much it just stays on. With the clap circuit you get the control your looking for.

0
None
KickBustermpilchfamily

Reply 5 years ago

Ι watched the clap circuit tutorial but it looked to complicated for me...maybe i'll give it a tray and see what happens! Thank you!