peak led for simple VU meter

[dmp]

Simple way to add a peak LED to this simple vu meter by PRR?

 

[JohnRoberts]

Simplest would be a LED and resistor in series with a zener diode or Vbe multiplier between the two opamp outputs, but the lack of a hold circuit would not give an easy to read display for narrow peaks.

I would suggest rolling something using a LM339 comparator (or the dual version)... surely there are many proforma schematics floating around.  You could also make something with a transistor or two... while the math will be easier with a proper comparator.

JR

PS: It seems this has been discussed before..