The LM3914 LED bar graph driver was an amazing chip back in the day. Along with the LM3915, its logarithmic cousin, these chips gave a modern look to projects, allowing dancing LEDs to stand in for a ...

The circuit was conventionally designed with eight LED audio level meter made out of two low power quad op-amps which utilizes LM324. Volume Unit – an entity equal to a decibel for expressing the ...

This circuit uses two quad op-amps to form an eight LED audio level meter. The op-amp used in this particular circuit is the LM324. It is a popular IC and should be available from many parts stores.

An example of a digital meter that was designed to display both VU standard response and peak tracking. Some excellent articles have appeared lately on the history and use of audio level meters in ...

Over the summer [ElectroSmash] put the finishing touches on the Arduino Audio Meter, a shield for the Arduino Uno that visualizes various aspects of an incoming audio signal on a set of four 8×8 LED ...