The EM Poll

Crossing the Finish Line

Feb 1, 2008 12:00 PM, By Michael Cooper

           

Stuck in a rut during mixdown? Here are ten tips for reevaluating your work so that you can stay on track.

FIG. 4: A brickwall limiter adds distortion to a track when it squares off the top of its waveform on peaks.

Silence Is Golden

Sometimes, no matter how much you tweak the mix, it just sounds bad in one or two sections. The mix is probably not the problem here. The culprit is the arrangement, and no amount of EQ, effects, or riding faders will help until you start ditching or replacing the problematic parts.

When you suspect the arrangement might be killing your mojo during a particular section of the song, mute individual tracks one at a time to see if ditching any parts improves the mix. Often, muting one or two tracks for just a few bars will clear out clutter and bring back the air in a mix, allowing more musically important parts their time in the sun.

You may find upon muting some tracks that the mix has improved but the song is left with a big hole in the arrangement. If time permits, don't be afraid to create and record an entirely new part to replace what's been ditched. Just make sure it's substantially different from what you got rid of, or you'll be back where you started. You just might come up with another hook that transforms the song.

Pull the Plug

If you've done everything you can to polish the mix and it still sounds bad, maybe you've done too much. With hundreds of DAW plug-ins available for processing, sometimes the temptation is to pile on the sauce to the point where the main dish loses its original flavor and appeal.

Used wisely, the right plug-in can wonderfully enhance the sound of a track. But many plug-ins also degrade sound quality in subtle ways that might not be immediately obvious (most often by reducing depth and nuance). Make sure the improvements and trade-offs sum up to a net gain.

If you've been tweaking a track's plug-in settings for a while and are still not satisfied with the results you're getting, try bypassing one or more plug-ins to see if the track sounds better with less (or no) processing applied. Maybe an overly dynamic vocal track will sound rounder and sweeter if you ride its fader up and down where needed, rather than beating it into submission with a high-ratio compressor. And a hazy guitar track that's having trouble cutting through the mix may not need an EQ boost in the upper midrange after all; there just might be too much reverb — or the wrong type of reverb — on the track. Sometimes less is more.

Hit Your Peak

Considering that it might take an entire day or longer to pull off a truly great mix having many tracks, it's no surprise that ear fatigue can often derail the process. Monitoring at low levels and switching monitors often to change your perspective can help keep you fresh. Equally important is to carefully watch your meters, especially those for your main stereo bus. Keeping tabs on your mix's crest factor on your stereo-bus meters will often point out problems with the big picture that tired ears have missed.

Crest factor is essentially the difference between a mix's average and peak levels. A mix that has a large crest factor exhibits big swings in level when percussive elements such as kick and snare drums strike (see Web Clip 2). Speaking generally about popular genres of music (and not classical music), a mix with a large crest factor will sound more rhythmic and, if the bottom end is in proper perspective, punchier. A mix with too large of a crest factor, however, will sound less full and not as loud compared with others.

A mix with a small crest factor typically causes stereo-bus meters to barely fluctuate at the top of their range (see Web Clip 3). Kick and snare hits may not even move the meters because those instruments are, in fact, somewhat buried in the mix. Such a mix is usually very loud, fatiguing, and deficient in rhythm and punch.

Natural sounds that have both an attack and sustain portion, such as a plucked acoustic guitar string, might produce a peak that is 10 dB or more above its average sustain level. A brickwall limiter can reduce the guitar's peaks so that they swing perhaps only 3 or 4 dB above the sustain level. But the trade-off is that a square wave is created on the peaks (see Fig. 4). That generates distortion.

The same principles apply to a mix's crest factor. A maximizer can be used to reduce peaks and raise average levels to make a mix sound louder, but that also generates distortion. The distortion may be subtle enough that it's not easily identified as such, yet it most certainly will fatigue your ears if it occurs repeatedly throughout the song. On the other hand, even a rock mix with a large crest factor will — all other things being equal — sound smoother, sweeter, and warmer.

Even without using a maximizer or brickwall limiter, a mix can end up with too small of a crest factor. All it takes is having tracks with sustained sounds cranked and drums and percussion buried in the mix. Such a mix will also sound fatiguing.

If you find yourself chasing endlessly after the proverbial warm mix and all the modeled vintage-EQ and tube-emulation plug-ins in your arsenal can't quell the edge, check out your mix's crest factor. If your stereo-bus meters' levels are swinging only 3 or 4 dB throughout the song, the guitars and keyboards might need to be lowered and the drums (and possibly the bass, whose optimal relationship to the kick drum — once it's dialed in — should be maintained) might need to come up in the mix.

Spend time analyzing the crest factor for mixes you admire and love listening to. Then aim to achieve a similar crest factor while mixing your own similar tunes. With practice and the guidance of your stereo-bus meters, you'll be able to move quickly beyond an edgy mix and arrive in warmer waters.

In the Can

The techniques I've detailed in this article should not only help you create a better mix, but also help you do it faster. Just as important, using these tools should increase your ability to recognize when you've made the mix as good as it can be. When it comes to an open-ended mixdown session, knowing when you've crossed the finish line is half the challenge.

EM contributing editor Michael Cooper is the owner of Michael Cooper Recording in Sisters, Oregon. Hear his mixes at www.myspace.com/michaelcooperrecording.

BONUS MATERIAL
Web Clips: hear audio examples and watch a video that demonstrates what sounds you might not hear—but can see—in a mix