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Need help with Music Sync to LED project

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mosaics

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Hi, I found out about this website from a friend and it really help him a lot. So hopefully this help me with my project too.
Im currently making an LED sync with music for my school project. I decided to do this project because of a video on youtube and it really looks cool!

This is the circuit diagram I found and tried it on multism:
**broken link removed**


And it worked using an LF347N IC OpAmp and TIP31A transistor. I transpose them to the ultiboard to make the PCB.

This is what I get:
**broken link removed**
**broken link removed**


The green and blackish-green wire is the left & right input connected to my computer headphone jack. And two reverse supply of 9V battery each on pin 4 & 11.
Well, it didnt worked this time....
I dont know where I go wrong and my professor dont even know what to do "orz
So Im left with the community on this site to point out my mistake and help me with the construction of this circuit.
Thank you.

PS: Ive tried the simple circuit with just the transistor, resistor and LED. But the professor wont accept that.
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I think the base-emitter diode of a transistor rectifies the signal and charges its filter capacitor so the transistor does not work anymore.
The filters should feed opamps or transistors with a high input resistance.

It is a shame that the circuit uses opamps that have an extremely high input resistance (because the inputs are Jfets) but the opamps are used as inverting amplifiers that have a very low input resistance of only 100 ohms. Then the inputs might attenuate the signals.

Fixes:
1) Make the opamps non-inverting amplifiers that have a fairly high input resistance.
2) Make the transistors emitter-followers (that do not rectify the signal and they have a fairly high input resistance).
3) Add a filter capacitor (100uF) across each supply voltage.
 
Is this a "light organ"?
**broken link removed**

thank you ronsimpson! lol, I didnt know it was called a light organ. Ive been searching for 'music sync to led' all this time and never found a good explanation. Hopefully I can find what Im searching for now.
Ill come back here if I run into any problems :D
 
If this was the 1960s:
Lay on you water bed, turn on you lava lamp, play music too loud, watch the colored lights from you light organ, and smoke weed.

I light organ divides audio into high/center/low frequencies and turns on lights.
 
Ron: I trade you the lava lamp for some weed...or is it the other way around? E
PS: This is a terrible circuit!
 
The color organ has wrong filters.
1) The bass should have a lowpass filter, not a bandpass filter tuned to only one frequency (a bongo drum?).
2) The midrange filter should be a highpass and a lowpass to pass a range of middle frequencies not a multiple-feedback bandpass filter that has a very narrow range of frequencies at its peak then a very gradual rolloff at each end.
3) The treble should have a highpass filter, not a bandpass filter tuned to only one frequency (a smoke alarm?)
 
So whats the correct schematic for light organ?

I was asked to redo the circuit on a strip board and have to be submitted by Thursday.
Im sticking with the original schematic since it worked on Multism (it will give me some extra points).
Now Im trying to figure out where should I connect all the grounds and where the input should be.
 
There are thousands of circuits for "light organ" out there, ready for googling. Maybee you should have asked earlier and taken your course in electronics somewhat more seriously (sorry, if that sounds harsh...)

RonS: Could a lava lamp show me where ND is? E
 
im guessing you are at the same uni as me as mine is the same project and due in on the same day. I have spent weeks on mine and have learnt about filters and op amps.

This is why i refuse to offer help as in my eyes you havent realy tried to learn like we are supposed to.
 
I have research all about them these past few weeks, thats why its finished like the picture Ive shown you. Like I said before, it worked on the multism but when I transpose them to the PCB, it didnt work. Thats why I would like some help to check if my input and ground are correct
 
Unfortunately it doesnt work. I have to make up for it by doing a report, then a summary for the presentation.
And whats a mokhtar?
 
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