I recently received a question from Devlin, who lives in North Carolina here in the states. In response, I thought it best to share the process I follow when exporting a final mix. In relation to his final mix, Devlin asks ...
I never know how to export my tracks, do I export as a .WAV or .MP3? What sample rate should I select, and what bit depth should I choose? I know that .WAV files are bigger but are they actually "better" quality than .MP3's?
Export a .WAV file in the same quality as your project
When a project is compete, I always export a .WAV file at the exact sample and bit rate of the original project. I record most of my projects at 48khz and 24 bits, so I would export a .wav at those sames settings with no dithering applied (for more information on dithering check out this post).
This is very important because the final step before distributing a project should be the "mastering process". This is often done to a stereo file (or several stereo files from your sub buses called stems) of the final mix. I prefer this step to be done at the same quality my entire project was recorded at.
Export a CD quality .WAV file as well
From here I take that same multi-track mix and export another .WAV. Only this time as a 44.1khz/16 bit file using the default dithering settings. I do this because that data and bit rate is the same as an audio CD. Also some mastering engineers prefer to master in the same quality that the final project will be distributed in. This is often the standard audio CD (though .MP3 releases are getting very popular with the era of downloading digital music today).
Doing this export simply gives me another mastering option. It also gives me a copy of my mix that requires no conversion to be burn directly onto an audio CD. This can be helpful to test my mix in other systems as well.
Export an .MP3 of the final mastered mix
Now, the question of .MP3 versus .WAV. In general .WAV is a much higher quality file than .MP3. Though really high .MP3 quality can get pretty close. I don't recommend using .MP3 as a final mastered format if you have .WAV as an option.
In my opinion .MP3 is best for a project that is already mastered or at the very least, ready to be distributed for others to listen to. It works great for download quality format because the file size is much smaller than .WAV. These smaller files can still maintain an acceptable level of quality for personal listening.
My preference is to use iTunes here to convert the fully mastered copy of my final mix to .MP3. At this stage I can also add my artwork and other embedded song info to the files themselves. This really helps to create that professional touch to my audio files.
What are your thoughts or comments? Please add them to the section below.
What do you gain in the quality of the final product by recording at the higher bit rate when you just have to dither it down for CD?
The biggest benefit is headroom for processing. When you apply effects and make adjustment at say 24bit/48kHz there is less chance for clipping and more dynamic range thus an overall quality increase as there And an overall noticeable difference in quality that does show in the final product. Plus there times times within the post production phase where dithering is also applied (like bumping down multiple tracks into 1 to save CPU). At this stage 24 bit is a great benefit to quality because of the extra headroom. Some guys bump down in real time and record directly to another interface at 16bit as this has no dithering apply that way at all. Then the mastering is done at 16 it in that case.