When you feel your mix is ready, disable those Mastering plugs and export the Entire Mix. Either re-import them into a new stereo track project strictly for Mastering

 
This is what I do Brian, and I have the same mastering chain on all of my current album projects.
 
They all get exported, individually with NO mastering Fx on them, and then re-imported as separate tracks at appropriate places on the timeline and there's my album.
 
I then have a similar chain of Mastering Fx on this projects master buss, so everything sounds the same as the individual songs.

"Are any of you using Waves plugins for that commercial polish during Mastering or any 3rd party Mastering effects for that matter?"
 
Yea BMOG, I'm using the Waves Gold Bundle. I just upgraded my computer to a nice new shiney AMD processed monster with Windows 8.1. Upgraded my X3 to X3 Producer, then decided to try and move my songs from the old computer...NIGHTMARE!!!  3 days later I can finally breath again. But the Win 8.1 is buggy, Producer is buggy, and yes I upgraded to the e version. My new machine is awesome, 8 core, 4.0gHz, 16mb ram, SSD hard drive, and an hhd 1tb for storage. But man this new windows is awful. Anyway, Waves, I love their plugins, Vitamin is just a killer sonic enhancer, their compressors and limiters are so transparent. The only thing that was bugging me was the constant checking for a valid license, but then I found the VST Settings under preferences and made the scan mode manual, so all was ok. I finally got my songs to work after several downloads, I truly believe it was the vst's causing all the issues, trying to get them switched over to the new computer and all messed things up. As far as mastering with Waves, I am one that blends the process of mixing and mastering, and I need to stop it. I will have a great mix, but I am so curious to hear it with limiters and compressors and linear eq and on and on, whatever makes it shine, that I will go ahead and add those things on the master bus. Granted, I will not export with these on the master bus, I read somewhere that when you export with compression and eq that your digital signal is forever changed and will not go back to the original signal. Is it true? I don't know, but I avoid it just to be safe. So in essence, I really haven't mastered anything yet. We have two tunes mixed, 3 being worked on, and when you meet once a week for 2 or 3 hours, it takes forever to do a cd.
 
\m/ >< \m/ 

There are many ways to approach mastering. Most of the time I find no one program does it all, so I have to work with mutiple programs. For example I might use WaveLab for its analysis, but end up doing crossfades and "surgery" in Sonar while using Sound Forge's shortcuts for auditioning sections.
 
To me the most important element of mastering is EQ. If that's right, the rest falls into place and little dynamics correction is needed. Then again, much depends on the material. Mastering classical is very different from dance music or industrial video soundtracks.

Yes Wave Labs analysis, this is worth the price of the software. Otherwise you are only guessing and working blind.
Find peak Level,  Global RMS Analysis, and spectral analysis are must have tools for mastering. 
The cool thing is most of Sonars mastering tools also show up in Wave Labs efx bin. 
 
Anyhow I just make my mix sound great and then export it. Open in Wave Lab , Master and burn with whatever. 
 
Once you've experience the tools it has you could not work any other way. 
 
Example, Long ending? scroll to  the spot you want, "ctrl/ End/ delete= done. 
Beginning still has count in? ctrl / home / backspace. = silence
 
It is just plain fast at these tasks. Sonar and Wave Lab are perfect Partners. Sonar is my 24 track Otari and Wave lab my 2 track mastering deck. 

Christopher D
Alright, I have a huge project (about 50 tracks and 10 buses) that has been fully mixed. I have the plugins assigned that I want on the master bus as well. So, for all intents and purposes this track is actually mastered, for better or worse.

IMO you should never combine the mix and master process at this stage. The mix shouldn't contain anything on the master bus (ie: compression, limiting, reverbs, dramatic eq, etc...). By having a "clean mix" ready you can do anything you want with it without damaging it. You are no longer locked to those initial decisions you made on the master bus.
 
EDIT: oops... I just noticed this thread is 1 year old... I usually try to avoid these.

+ however many for making mixing and mastering separate processes.  I use an exported mix at the project rates (bit depth and sample rate) in Sound Forge.  And external hardware in addition to whatever digital effects.
 
One of the things about the two-step processes is you'll quickly see if your project has 5 minutes of silence appended to it, even if you bring it back into a new SONAR project.  And as others have said, there shouldn't be that much left at the mastering stage - a little eq and compression to raise the overall volume and a little tone (to match up for a multiple song CD), and any editing even if it is only to top and tail.
 
@

With tunes that will not be used for real distribution (CD printing/sales), you may want to give the online robot mastering at www.Landr.com a try. The mp3's that it mails back to you are free with the basic account and it sometimes delivers a halfway decent job (many complain that sounds "hyped"). If you want uncompressed 16bit/44k wave files then there is a small fee involved.
 
I usually try to do it myself in a DAW with Ozone-T-racks-other goodies,  plus run the song through AAMS, and also give landr.com a chance. The one that delivers the best product gets the nod. But I never charge people for this type of mastering, If they want to pay for it then I point them to a professional.

2 things:
I always have Start and End markers on my projects.  Then I can quickly
   select all,
   go to start marker, set from=now,
   go to end marker, set thru=now,
   file->export.
 
I would never have '5 minutes of silence' before or after cause it's always correct. 
(I wish there was an option that meant that export 'knew' where the start and end points were).
 
Also, I DO have my mastering chain on the master out channel, but I globally turn off processing on that channel until mastering time.  That way, I can A/B mastering or not, always have the current edit/mix (without exporting) and I can tweak the mastered mix in real time (just in case something clips). 

Thanks guys for the recommendation of AAMS mastering system. I tried downloading the free version with the Microsoft Edge browser and it wouldn't download, so I tried it with the Chrome browser and it worked perfectly. I tried processing a couple of my test recordings, burned the resulting file to cd and played them in my truck's sound system....sounded Awesome !!!!!!!!!!!!!!!!!!!!! I compared them before and after and there was quite a bit of difference,,,sounded great !! Sounds great on my headphones as well !!

Here's a sample of a recording a friend and I made then mastered it in the AAMS software....
 
http://www.soundclick.com/player/single_player.cfm?songid=13448952&q=hi&newref=1
 
 
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