Mixing Tips:
Students often ask me for tips about how to mix a song effectively. Mixing is a full-blown art in and of itself. There is no one way to mix a track well, nor are there rules about how to mix a track correctly. However, there are decent guidelines and best practices on how to proceed and get started.
First of all, you will want to use a quality program like ProTools or Logic Pro. There are numerous other programs that will allow you similar amounts of control over your work. Pro Tools is considered the industry standard for media creation. Personally, I use LogicPro, as I feel it has the best value in terms of features per dollar. Lesser programs like Audacity and GarageBand don’t give you sufficient control of your tracks to fine tune a mix. That being said, if all you can afford right now is a tool like Audacity or GarageBand, then do the best that you can with the following guidelines, and save your pennies up for a better tool.
Put individual EQs (Graphic Equalizers) on all of your recorded tracks. Use them to filter out all of the frequencies below the given instrument’s lowest frequency, as well as all of the frequencies above its highest overtones. In Logic Pro, you can click on the analyzer button in EQ plugins so you can see what frequencies are active in a track, which can help you filter out external noise. You can make small boots of frequency bands that make the instrument sound better, or more characteristic. You will likely need to pull down the master gain in the EQ a bit if you’ve done any boosting to prevent distortion / clipping. Any synthesized / sampled materials or loops that are resident in your DAW (Digital Audio Workstation) software don’t really need and EQ, unless you are going for a particular effect. For more information on the effective use of EQ you can read my post on “tips for using equalization.”
Put compressors on any recorded voice, guitar, and bass tracks. The default setting I use is a 3:1 ratio. Make sure that your threshold is low enough that compression kicks in when the track is at its loudest, but not so low that it is kicking in most of the time. Your compression plugin should give you visual feedback for when the compression is kicking in. If you are using both compression and EQ on an input channel, place the compressor before the EQ, as the compressor can undo some of the dynamic changes you set in your EQ.
For music in a popular vein (pop, rap, hip-hop, heavy metal, rock, etc.), you can also put a compressor on the output channel as well. This will help avoid clipping on transients in your final mix. Avoid using compression on the output channel in classical, jazz, or folk music, as overuse of compression diminishes dynamic contrasts between sections (for that reason, I personally avoid using it in popular tracks as well).
When you have more than one track of a given instrument playing simultaneously, use the opportunity to pan them to increase your stereo image. Pan multiple instrumental tracks as far as you can without the panning sounding obvious or artificial (unless you want it to sound artificial). A nice starting place to try is panning halfway, which would be + and – 32 on a scale of +/- 64. A more subtle setting might be + and – 16 on the same scale. Sometimes panning hard left and hard right can work well for some tracks. In addition to panning you can also use EQ to help tracks using the same instrument sound distinct from one another.
In a typical mix, the lead vocals and bass should be centered. If you are using a single track for the drums, that would also be centered as well. If you have recorded an acoustic drum set using a standard four mic setup, put the kick drum in the center, pan the snare slightly to the right, and hard pan the right overhead mic (audience perspective) to hard right, and left overhead mic hard left. This gives you the audience perspective on the drumset. If, for whatever reason, you want the listener to hear from the drummer’s perspective you would put the snare slightly to the left, the right overhead mic in hard left, and the left overhead mic in hard right.
Another mixing trick is to use your eyes in addition to your ears. Logic Pro has meter plugins, and personally, I like to put a multimeter on the output channel. This has two advantages. One is that I can see what frequencies are active. For instance I may learn that need to make the track brighter, that there’s not enough bass, or that there’s too many mid frequencies.
The mulitmeter plugin also has correlation meter, which allows you to check your stereo image. When the meter is all the way to the right that means that the left and right channels are identical, meaning that you effectively have a mono track with no stereo image what-so-ever. If it goes left of center (into the red), it means that you are starting to get some phase cancellation between your channels, which can deaden some frequency content. The ideal place for the correlation meter to be is just to the right of center, which means you have are rich stereo field that doesn’t have any phase cancellation.
Voice can be a challenge to mix. Voices often require a lot of plugins. In addition to EQ, a voice may require some pitch correction. Voices that are thin in quality can be fattened up in three ways: through doubling, delay, or reverb. Reverb is the most common way voices are fattened up in popular music. You may read my article, “Tackling Reverb,” if you need some help fine tuning your reverb settings.
Doubling is one of my favorite ways to fatten vocals. Simply put, you record the vocals twice. Pan one take either slightly or fully to the left, and the other either slightly or fully to the right. If you like the sound of doubled vocals, but didn’t have the time to do multiple takes, or one take of the vocals was significantly better than the others, you can fake the sound of doubled vocals, by panning copies of the vocals hard left and hard right, and putting a short delay (around 50ms) on one to the two copies.
If your track still sounds a bit dull after all your EQing, mixing, and balancing, you can add an exciter plugin on the output channel. Exciters by definition add volume by emphasizing high harmonic content. If you were careful to optimize your mix, you won’t have the headroom to add this effect. Thus, you can add a compressor on the output channel first, and pull the volume of the whole track down slightly after the compression, which should leave you the headroom to add an exciter. Alternately, if you feel the whole track doesn’t need an exciter, you may wish to add it to the vocals and / or the guitars to brighten the track a bit. This can be done on the input channel, or by busing to another channel.
Another way to look at mixing is to look at it as a process. It is advisable to start with the vocals. Vocals are by far the most important track in nearly all popular music, so starting with them gives you a structure to build around and to elaborate upon.
Solo out your vocals track by track. Listen to them all the way through to check for quality. Edit out lip smacks (which sound gross), and possibly even breaths. It can be fine to leave breathing in if you feel it ads to the human or emotional quality of the take. Otherwise, it is just more noise.
Add EQ, compression and any other effects you intend on using (reverb, pitch correction, etc.). Pan the vocal tracks the way you ultimately intend them to be panned. Generally speaking, put the lead vocals in the center, unless you are double tracking the vocals. You can spread multiple backing vocal tracks across the stereo spectrum, dialing it back a bit if it sounds too artificial.
Listen for distortion or clipping on each your vocal tracks. Adding plugins often adds volume, and panning a track off center often puts heavier load on one of the channels. Thus. if your vocals did not clip initially, they might clip after all these changes. You can adjust by bringing down the master volume in the EQ. Listen to all your vocal tracks together. Make sure the balance between lead and backing vocals is good. You can soften backing vocals by adding reverb. Again, check for clipping and distortion on the output channel. You can adjust by bringing down the master gains in the EQ.
Do the same process for every instrumental group. That is listen to each instrument separately, editing, panning, EQing, and processing along the way. Then listen to each instrumental group together. Each time checking for clipping / distortion. I tend to mix and balance the instruments in the order: voices, drums, guitars, bass, and everything else. However, it doesn’t matter which order you do them in. Once you finish an instrumental group, check it with the rest of the mix that you’ve done so far. Check the balance as well as clipping / distortion.
Once you think you’re approaching the final mix, you can check the balance using a simple trick. The volumes of the tracks should be arranged such that the most important track is slightly louder than everything else, with the volumes decreasing, as their importance to the track decreases. In pop / rock music, that typically means that vocals are most important, followed by the drums, guitar, and bass in that prioritized order.
You can check this very simply by playing the mix at a very low volume. When you are listening to the track at an almost imperceptible level, you should still be able to hear the most important track (usually the vocals). Gradually increase the volume. You should hear the instruments enter one by one in order of importance. If the instruments enter in the wrong order of importance, readjust your balance, and try again until the instruments appear in the correct order of importance as you gradually turn up the volume.
Another thing you can do at this point is to put a multimeter on the output channel. Use both your eyes and ears to make sure you are using the entire frequency spectrum in a balanced way. To put this another way, check to make sure that the bass isn’t too strong, that the high frequencies aren’t too sibilant, and that there are adequately balanced mids.
You can also check the stereo balance. Are you using the entire stereo spectrum without getting any phase cancelation? Does your stereo field sound natural or subtle (unsubtle panning can be appropriate for specific effects, or for novelty arrangements)? If there are problems with either the frequency or stereo spectrums, adjust your balance, mix, and possibly the EQ for some tracks and try again.
It is always best to listen to your mix on the highest quality speakers or headphones you have available to you. However, many people listen to music in unideal situations, for instance using earbuds, or on a car stereo system. It’s actually a pretty good idea to also listen to your mix using one of more less than ideal playback system.
Finally, if you have the luxury of time on your hands, put the mix away when you feel it is done, but come back to it the next day. Listen to it again. If you don’t want to change anything, it is finished, otherwise, tweak it, and come back to it the next day with fresh ears.