In this series we’ve covered just about every process used in a typical mastering chain from buss compression and mastering equalisers right through to stereo enhancement and brick wall limiting. Now as we come to the end of the process we’ll take a step by step look at how to export your master ready for distribution.
Although the screenshots in this tutorial maybe from a few different DAWs the techniques used are 100% generic and can be used in any software. I haven’t included any audio clips here as these techniques are mainly related to workflow and extremely subtle audio treatments. Think of this more as a final checklist for your mastering sessions.
Step 1: Check Your Gain Structure
It may seem obvious but you need to ensure that nothing is clipping at any stage in your mastering chain. So right from the actual mix or file your are using, through the entire plug-in chain and finishing with the final output, there shouldn’t be a clip light or over in sight.
A few of these might slip through the net in the mixing stage but it’s crucial that they don’t appear when mastering. Maintaining a super clean signal is crucial here.
Checking the gain structure in Record’s mastering chain.
Step 2: Check Your Settings
Next up perform one last check of your plug-ins settings. When doing this it’s a good idea to listen to your master with specific treatments bypassed and then activated. This will allow you to hear how much processing is being added. Sometimes things can get out of hand and too much processing is never a good thing.
Also look out for rogue settings that have crept into your chain. Sometimes you may find that you have experimented with something extreme or unusual and left it switched on. Now is your last chance to catch any mistakes like this, so it pays to be thorough.
Some more complex plug-ins may need one final check before exporting.
Step 3: Check Your Output and Dynamic Range
Before you move onto actually exporting your final master check your final output level. If your limiter is set correctly then everything should be taken care of and you should be experiencing no overs or clipping at all at this stage.
If you are new to the area of mastering limiters you can check out Part 5 of this series to get a good idea of what you should be doing. Simply put you should check that there are still some dynamics in your mix. Too much limiting will squash the life out of your master and give you an ear bleedingly loud result.
A dedicated dynamic range meter may be worth using.
Step 4: Applying Dithering
We are now ready to export the master. In most DAWs you will now be presented with a number of options. Some applications will offer more features than others here but there are always a few key things to look out for, one of these is dithering.
Pretty much every DAW out there will feature dithering options and it’s something my students ask about a lot. Simply put dithering is a process used when moving to lower bitrates. For example if we are working at 24-bit (either at the mixing or mastering stage) we will need to move to 16-bit. This is so our final master is suitable for MP3 conversion and burning to various media.
The move from 24 bits (or higher) requires a fair amount of digital data to be removed. In normal circumstances this would result in a lowering in quality but dithering uses various complex algorithms to ensure that what you hear in your final master is nearly identical to that of your 24-bit premaster.
The whole process is pretty clever and there are a number of different algorithms floating about between the various DAWs. You may see Pow-r or Apogee dithering options, or your chosen application may simply have a dithering on or off option. Some applications, such as Cubase, rely on plug-ins that are inserted in your mastering chain to perform their dithering. Whatever the options presented to you its worth knowing a few tricks.
Cubase 5 includes an Apogee dithering plug-in out of the box.
If you are already working at 16-bit then you don’t have to dither, only use the dithering feature if you are moving from a higher to lower bit depth. Also only apply dithering once in the whole mixing and mastering process. So from the tracks conception to the final master there should only be one round of dithering applied. Most of the time it’s a good idea to do it right at the end.
With this basic knowledge of dithering under your belt you are ready to move ahead, set the final parameters and export your work.
Some DAWs such as Reason and Record have much simpler dithering options.
Step 5: Other Export Settings and File Formats
Full blown DAWs such as Logic, Cubase, Pro Tools and Digital Performer offer a number of other options at the export stage and you may want to make sure they are set correctly at this point. For instance you will need to set the format of your export.
The file formats available will vary drastically on your DAW but the two main flavours people work with are Wav and Aiff. These used to be specific to Mac and Windows but in all honesty people tend to switch between the two now regardless of platform, so usually either one is fine.
Saying this some distribution companies and record labels (both digital and physical) have specific guidelines and requirements on the sort of file formats they like to receive, so it’s well worth checking before you send your files to their intended destination.
Logic Pro 9 offers a whole host of features when exporting your masters.
Step 6: Final Inspection and Trimming
With your export finished it’s worth giving it a final quality control check. I like to load the export into a secondary sample editor to get a full overview of the file. Applications like Peak Pro, Wavelab and Soundforge and are excellent programs for this stage. These apps tend to give you a better overview of the whole file and any issues are immediately highlighted.
If you have left gaps before and after the main body of your audio (which I strongly advise), you will need to trim the audio down and apply short fades to ensure that there are no clicks and pops at the start and end of your track. With these final edits completed you should be good to go and have a master you are proud of!
A final check and trim in your audio editor and your done.