Thanks for the reply Jeff. Very interesting. So since Sonar can have peak and RMS meters this is more for moving either BEFORE all your inserts or between them?

Yes definitely. For example Studio One allows you to insert a plugin before the signal even reaches the track. Way back in the signal chain. So you can put one of their meters there or a third party VU. You can still use an insert though it is just that you will have to enable input monitoring in order to see it working which is also fine too.  And yes to between them as well.  Good idea if you have a plugin chain.  Some plug-ins will just add gain for example to a signal and it is good to be aware of it.  Back it off after the plugin and get it back to the ref level.  A lot of plug-ins have output level controls too making this easy.  But even if not you can always insert a plugin to subtract or add gain straight after a plug-in.
 
Everyone knows I am pretty well a big fan of VU's!  You can certainly produce without them it is just with them I feel it is all a bit easier and more straight forward.
 
If you premaster say a whole group of songs so all the mixes are at the same rms level then mastering is a snap because all your tracks are going to be the same volume before you even master and that is a nice place to be.  You are now not chasing some tracks to be louder and pull others down. You can almost use the same mastering chain for all of them.
 

Thanks for all the info Jeff. Gave tnipe's idea a vote over in the bakery. Though I suspect I'd need a tutorial to figure it out if Cake decides to add it ever!

Caa2
Fun fact: An actual VU meter only displays RMS at 1kHz. In other words, VU meters do not display the RMS of musical or spoken word content.
 
Furthermore, VU meters are only appropriate in an analog domain as they are intended to describe actual real life voltage so that one may infer actual real life amperage. They just sort of play make believe as a proxy in the digital domain.
 
A great upgrade for SONAR will be the provision of LUFS meters.
this message will probably self destruct.

This post has already self destructed and is total rubbish.  First.  Frequency response of my VU (hardware) meter is like from DC to well above hearing. 30Khz or more.  Flat as a tack as they say.  So it shows correct rms values over a super wide range of frequencies.
 
It was originally designed for voice and voice is actually the perfect program material for a VU.  It is one area where it excels.  Music wise it does an excellent job of showing rms values of music.  I agree it is not exact but very very close.
 
It is super useful in a modern digital recording medium.  Use it and you will find your tracking and mixing will improve out of sight.  It is an excellent modern day tool.
 
The LUFS meter is also an excellent tool.  It shows you volume over the whole course of a piece of audio which is also good to know.  For a track that is consistent a great VU reading will give you a very similar LUFS reading.  (LUFS is about 2 down from VU rms. eg a K-14 track that is consistent is about -16 LUFS. For consistent level tracks they are very related to each other.)
 
 

Thanks guys for your responses. I'm going to check some of these out this evening when I get home!!!
I need to dig around because I think I may have the PSP VintageMeter that Jesse G mentioned somewhere in my "archives". Thanks again!!!

The Grim
the tbproaudio vu meter has copped quite a bit off flac because it is 'apparently' inaccurate etc, whether that is true or not is not for me to say, just putting it out there http://www.kvraudio.com/f...c.php?f=6&t=476712
 
i use the klanghelm vu meters and they seem to be pretty good. also a fan of the studio one vu meters, and like the fact that you can have the 'mini' version expanded and visible for each track or bus. probably not as good as the klanghelm, but very useful none the less (of course not for sonar)
 
psp triple looks ok, and for $29 most likely worth a look seeing how a couple of knowledgeable people above recommend it. would like to hear jeff evans's view on it (nudge, nudge)

I read that TBProAudio mvMeter thread over at KVR (caution: long, with some name calling).  The developer has already patched it twice this month in response to the test reports from the KVR metering "expert", citing apparent inaccuracies.
 
It seems that the current version 1.0.2 is now usable, if you are willing to overlook the alleged "blatant ripoff" of Klanghelm's design.  http://www.tb-software.com/TBProAudio/mvmeter.html

Please refer to the where you got the quote from. At first you said they were only accurate at one frequency which is obviously completely wrong.
 
The VU meter is designed to read voltage in the analog world, not current. (Let me clarify here. Yes a very long time ago it was showing power transfer over a 600 ohm telephone line but since then the impedances that exist in audio signals being transferred from point A to point B are much higher now hence the fact that it reads voltage these days not current)
 
In the digital world it shows very well what the average or rms level of the signal is making it a fabulous and seriously tool.
 
Please click on this link, unzip and read the following attached article. You might learn something about them and even change your mind.
 
https://drive.google.com/file/d/0B_2Jb7O_b5BkeVB3dFVsUm8zelE/view?usp=sharing