Real-time Mastering Within Your Digital Audio Workstation

A major difference between mastering in a MIDI + Audio sequencer and using a digital audio editor is that you have the option to adjust mastering processors (which affect the final mixed output) as you mix. With digital audio editors, you are always working off-line with a previously mixed file. However, there are advantages and disadvantages to both methods. The process of mixing is daunting enough without throwing mastering into the equation; however, mastering while you mix means you know exactly what the final version will sound like.

But remember that a huge part of conventional mastering is about involving someone who can be more objective about what needs to be done with your music. Unless that person can sit in on the mix and adjust the mastering processors, you're better off giving them your files and some space to do their job right. Mastering ReducingPeaks Automation envelopes can reduce the odd rogue signal peak, thus opening up more headroom and allowing a hotter sound without you having to use as much dynamics processing.

If you decide to master as you mix, you'll be putting your mastering processors in busses. This is because when you create a non-surround multitrack project, eventually all the tracks are going to dump through a mixer into a master stereo output buss. As with individual channels, this should have provisions for adding plug-in effects. How effects are accommodated depends on the program; for example, with Cakewalk Sonar, the busses have standard effects slots, just like tracks. But Steinberg's Cubase SX has a few extra touches: both pre-fader and post-fader slots for effects, as well as excellent dithering algorithms for cutting your high-resolution audio down to a lower bit resolution. (If a program doesn't include an effects slot after the main output level control, you may be able to feed one buss into another to achieve a similar signal chain — insert the effect into the second buss, and control overall level at the output of the first buss.)

Once your plug-in effects have been added and edited as desired, you have three main options to create a mastered file:

Render (also called bounce or export) the track to hard disk. This reads the signal at the final output, including the results of any effects you've added, and writes the file to hard disk. This is your final, mastered track. However, it still needs to be assembled with other tracks to create a complete CD.

Send the output to a stand-alone CD or DAT recorder. This will record the final, mastered song although, again, you'll still need to assemble these.

Send the output through analogue mastering processors, record their outputs into two empty tracks in your multitrack, then export those tracks to your hard disk. (See the 'Adding Outboard Processors To A Multitrack Host' box for more on this).

Of course, if you choose to do real-time mastering, you'd better get things right the first time, because if you want to make any changes later you won't be working with the raw mix file. For example, if you decide there's too much multi-band compression, you won't be able to undo this, and neither will any mastering engineer; you'll have to do another