Its very interesting and awesome to see lights dancing on music beats....
So lets first check this out...
such that not only LED's dance on music but we too... ;)
Step 1: What You Will Need
1) 5m LED strip (one or two as you wish)
2) Adapter < 240V input and 12V output> (one piece)
3) Breadboard(one piece) with some wires for connection
4) 3.5mm Y splitter jack i.e with one male and two female points (one piece)
5) One 3.5mm jack (with one wire to ground and one wire to left or right)
6) Diodes IN4007S (2 pieces)
7) 100K ohm resistor (2 pieces) , 1K ohm resistor (1 piece) , 5.1K ohm resisor(1 piece)
8) LM324N Quad opamp (1 piece)
9) TIP31C transistors or TIP41C (1 piece)
Note1: If you have taken 2 or more led strips then you need to connect parallel to the first led strip.
Note2: Take either TIP31C or TIP41C (here TIP 31C is used)
Step 2: Use of Adapter
The Adapter must be correctly rated as discussed before.
Higher output value can burn the circuit.
-ve part of 12V output will go to the ground of the circuit.
+ve part will go to the 4th pin of the LM324N and to the +ve of the 5m LED strip.
Step 3: 3.5mm Y Splitter Jack and 3.5mm Jack
The Y splitter will have one input from the circuit
and one input fromm the speaker. The 3.5mm jack of Y splitter will be placed in the mobile or laptop.
The 3.5mm jack will have open end with one wire for ground and other for left or right connected to the circuit.
It is clearly shown in the following circuit diagram.
Step 4: Circuit Diagram
This free hand circuit diagram shows everything clearly.
Keeping in mind the previous points,
follow the circuit on your breadboard and its done..... (Y)
Step 5: On Completion It Will Look and WORK Like This
Step 6: PCB View
Once completed, you can draw the same circuit on a small PCB so as to fix it permanently.
This pic is one of its view.
It will require some sort of soldering. But this is the last part.
It would be better to focus on a breadboard as a beginner.