mzuther has released traKmeter, a loudness meter for correctly setting up tracking and mixing levels.
Most digital audio equipment only has peak meters. This is understandable as you want to avoid digital clippings by all means. However, the lack of average meters makes correct gain staging almost impossible.
For gain staging, you need average meters or – even better – a combination of peak and average meters. And this is were traKmeter comes in.
traKmeter has an average level meter that is centered around -20 dB FS RMS and a peak level meter that is aligned to -9 dB FS. It comes with extensive documentation, supports stereo and 8-channel audio signals, has two scales, two ballistics modes and is easy to use. Additionally, all meters have been thoroughly validated.
traKmeter is free and available as a VST effect plug-in for Windows and Linux.