LED level indicator powered directly from the speaker

A very simple light level indicator without transistors, without microcircuits and without a board can be quickly assembled in a couple of minutes. It does not require additional power and is powered by the sound of the amplifier. Connects directly to the speaker. Such an indicator can be built into a music speaker and make it more original, or into the amplifier housing.

Will need

• LEDs - 10 pieces -
  
• Diodes 1N4007 - two pieces -
  
• Diodes 1N4148 - 9 pieces -
  
• Resistors 330 Ohm - 10 pieces -
  
• Capacitors 470 uF 16 V - 2 pieces -

Making an LED level indicator

We break the bar and drill holes at a certain distance. Install in holes LEDs.

We solder the negative leads into one common one.

We solder a current-limiting resistor in series to each LED.

We take 1N4148 diodes.

Solder them between resistors.

We solder two capacitors together in series. Plus to minus.

We solder them parallel to the negative terminal from LEDs and the last diode.

Solder the 1N4007 diodes. This will be a doubler.

We solder the power wires, they are also the output from the audio power amplifier. One to the middle of the capacitors, the second to the middle of the diode.

You can connect such an indicator directly to the dynamic head.

Flashes depending on the music level: the louder the sound, the higher the light bar.


You can clearly see how this indicator works in the video below.

Watch the video