8 Stage LED VU Meter:  (Circuit / schematic design added 6/06)

Analog VU Meter:  (circuit / schematic added 6/05)

Audio LED VU Meter:  built around discrete components (Electronic circuit added 5/02)

Audio level meter (VU Meter):  This circuit uses just one IC and a very few number of external components. It displays the audio level in terms of 10 LEDs. The input voltage can vary from 12V to 20V, but suggested voltage is 12V. The LM3915 is a monolithic integrated circuit that senses analog voltage levels and drives ten LEDs providing a logarithmic 3 dB/step analog display. LED current drive is regulated and programmable, eliminating the need for current limiting resistors. The IC contains an adjustable voltage reference and an accurate ten-step voltage divider. The high-impedance input buffer accepts signals down to ground and up to within 1.5V of the positive supply. Further, it needs no protection against inputs of ±35V. The input buffer drives 10 individual comparators referenced to the precision divider. Accuracy is typically better than 1 dB.  (added 09/05)

Digital volume Control has log taper:  04/11/02 EDN Design Ideas  /  (added 1/05)  Digital potentiometers provide a compact and convenient way to attenuate audio-amplifier signals. However, most such potentiometers suffer from at least one flaw: a nonlogarithmic step increment. To avoid this problem, a user must usually step the potentiometer in a nonlinear sequence to simulate a logarithmic taper. ...

Digital Volume Control:  based on DS1669 Digital Pot IC (Electronic circuit added 5/02)

High Resolution Volume Unit Meter Simplifies CD Recording:  06/21/01 EDN-Design Ideas / (added 5/03) Digitally recorded music on CDs offers superior quality to that recorded on vinyl records or tape, but most prerecorded CDs have an annoying characteristic: The average volume levels of the recorded signal can vary by as much as 14 dB from disk to disk. Significant variances, such as 4 dB, can occur from track to track on a single CD. This variation can be a problem when recording your own CDs because you can end up with large variations in loudness between songs....

Infrared Level Detector:  Useful for liquids level detection and proximity devices Up to50 cm. range, optional relay operation (Electronic circuit added 4/05)

LED Audio UV Monitor:  logarithmic scale with3 dB steps, based in LM3915 IC (Electronic circuit added 5/02)

LED Bar VU Meter:  (circuit / schematic added 2/03)

LED Barograph Driver:  (Electronic Schematic / circuit added 4/02) Fair Warning: this site has pop-up ads

Mono VU Meter I:  (Electronic Circuit diagram added 03/03)

Precision Audio MilliVoltmeter:  Measures10mV to50Volt RMS in eight ranges Simply connect to your Avo-meter set @50µA range (Circuit added 9/04)

Sound Level Meter:  (added 7/05)

Three Level Audio Power Indicator:  Battery-operated Three LED display that connect it to loudspeaker output (Circuit added 9/04)

Understanding Peak Reading Meters:  includes1-example circuit diagram (Electronic circuit added 5/02)

VU and PPM Audio Metering:  circuits using analog needle meters (Electronic circuit added 5/02)

VU Meter Amplifier:  (Electronic Schematic / circuit added 4/02)

VU Meter:  5 led VU meter, in PDF format, includes circuit board, text in Finnish (Electronic circuit added 5/02)

VU Stereo Meter:  will indicate the volume level of the audio going to your speakers by lighting up LEDs, based on LM3915 IC (Electronic circuit added 5/02)