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 analog VU (volume unit) meter is a splendid moving-coil measuring instrument. It is a passive electromechanical device displaying a representation of the signal level in an audio equipment. Even ...

It used to be a must-have on any hi-fi, a pair of moving coil meters or LED bar graphs, the VU meter. Your 1980s boombox would have had them, for example. VU, for “Volume Units”, is a measure of audio ...

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. The unbridled development of radio broadcasting in the 1920s and 1930s demonstrated the need to ...

Forbes contributors publish independent expert analyses and insights. Technology journalist specializing in audio, computing and Apple Macs. One thing teenagers love is playing loud music. Another ...

Before starting Techaeris, I didn’t think too much about headphones, like many people I just picked up a pair of cheap buds and went about my day. It wasn’t until I started testing headphones of ...

British audio experts Meters Music’s new Cubed speaker system is unashamedly cool, due not just to the minimalist design, but mainly because of the working volume unit (VU) meter built into the body ...

One of the coolest things any sound system can have is some kind of musical visualization. Thumping level meters that pump with the volume are a great example, and were particularly popular in the ...

VU is an abbreviation for volume unit. Thus, a VU meter is a device for measuring the level of sound intensity with audio equipment, such as amplifiers and tape recorders. Although the measurements ...