Tech Tip:Mastering with All-In-One Studios
They used to just record audio, but today's all-in-one studios can also do mixing, CD burning, and even mastering.
By Craig Anderton
Back in the analog age, a "studio in a box" simply had a mixer and multitrack recorder. But in the digital age, you're likely to find effects, automation (snapshot, and on more expensive boxes, even moving faders), connections for external storage, and now, even CD-R or CD-RW drives so you can take a project from plugging in your first instrument to burning a CD for the band members.
As equipment has gotten better, though, so have the technical standards by which music is judged — when you burn a CD, it had better stack up to commercially-available ones. Unless you have mixing chops of the gods, the only way to get that kind of pro veneer is to master your final mix.
As a result, some all-in-one studio products — especially those with recordable CD drives — now include effects algorithms designed specifically for mastering. As one example, let's look at Korg's D1600, which includes several tools to help you create the best possible-sounding final product. In addition to traditional insert effects, the D1600 also includes a Final Effect slot where you can insert effects that shape the overall mix.
The Two Crucial Mastering Effects
For starters, the D1600 includes the two most needed mastering effects: multiband parametric equalization to correct for frequency response problems (e.g. increasing articulation through a slight upper midrange boost, or reducing "muddiness" by trimming back the bass), and dynamics control.
Dynamics is the key to obtaining today's controversial "hot" sound, which places great importance on creating as loud a mix as possible.
Using EQ on your entire mix may be unnecessary if you properly equalize individual tracks first. In addition to the channel EQ, which is good for general tone-shaping, Insert Effect #I027 (4-band parametric EQ) can provide very sophisticated EQ control for individual channels. To process the overall tonal balance, you can insert #F010 (parametric EQ) as the Final Effect. However, as the D1600's mastering-oriented dynamics processors also include basic EQ options, you'll probably want to use the Final Effect slot for dynamics processing so you can control both dynamics and EQ simultaneously.
Any mix's maximum level depends on the available headroom — peaks that exceed it create distortion. Dynamics control reduces peaks, thus opening up more headroom. You can then increase the overall level until once again, the peaks hit the maximum possible level.
The D1600 offers several dynamics effect presets (#F001 - #F008) for the Final Effect slot. The first four are based on stereo compression (Effect DY1). Compression causes a change in input level to create a smaller change in output level. With stereo mixes, compression gives a punchy, "pop music" sound.
The other four presets are based on stereo limiting (Effect DY2). A limiter limits peaks, but doesn't affect the dynamics of lower-level signals. Subtle settings give a more "natural" sound than compression, so limiting is a favorite for acoustic music (jazz, classical, etc.). Limiting also acts a "safety valve" to make sure signals don't exceed the maximum available headroom.
Extreme amounts of limiting or compression produce a very "hot," loud master. This is popular with dance music, because DJs want the minimize track-to-track level variations as they segue from one tune to another. However, you have to be careful. Dynamics processors can't repeal the laws of physics; push them too hard, and you'll end up with distortion.
Sometimes, mastering engineers are called upon to do more of a salvage job than a simple enhancement. Live recordings, for example, may need sophisticated EQ and dynamics, which is more than you can fit into the Final Effect slot.
The solution is to use the D1600 more as a signal processor than a recording device. For example, run your two-track master into two inputs of the D1600, and use parametric EQ for the insert effect slot. Multiband limiting (DY3) might also be appropriate as an insert effect if the dynamics vary too much.
Next, for the Final Effect, insert dynamics processing to produce a smooth, hot-sounding master...then burn your CD. It's amazing how much some judicious processing can enhance material you thought might not be even useable.
Be aware, though, that mastering is a subtle process. A few dB or EQ or dynamics control is usually all you need. Higher amounts will unbalance the overall sound — if you boost the bass a lot, for example, then the treble will sound thin by comparison. This is why mastering is considered such an art: it's all about subtle changes adding up to a major improvement in the sound.
There's no guarantee that using mastering tools is going to produce a great master recording, any more than buying a guitar is going to make you a great guitarist. In either case, practice makes perfect. But in the case of all-in-one studios, it's at least nice to know that the tools are there for you to use.