* Sparks *

'roots keep me from falling to the gravities'

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Mixing, Part II: Drums

Drums are split into five subgroups: kick, snare, toms, cymbals, and hi-hat.  Each one has a distinct application of compression, EQ and limiting plugins.  Even though the same two plugins are used several times across the instruments, each time they have a slightly different purpose.

All of the plug-in screenshots used are from the project file for “Traps”, the opening track of my debut album.  I used these settings (or slight variations thereof) for the entire album.

Since I know that many people do not use the same DAW software that I do (Logic), I will attempt to focus on the concepts and settings that are universal to effects plug-ins like compression and EQ, rather than specific features of Logic (though at points this will be unavoidable).  This should allow you to use this information not only in Logic but also in other DAWs that implement these realtively universal plugins.

KICK

Here’s an overview of the series of plugins (or “signal chain”) used for the kick:

Kick signal chain

This is a screenshot from Logic.  The plugins are highlighted in blue near the top (the one in grey, “RBass”, is one that I tried but ended up disabling for the final mix).  At the bottom in the “I/O” section is the software instrument in blue (Groove Agent) and the output in grey (Bus 26).  It just so happens that I don’t do anything in the bus for the kick, so in this case this is equivalent to sending the kick to the main output (“Out 1-2”).  We’ll see buses heavily utilized for other parts of the kit.

Groove Agent is the least portable part of this channel strip, so I’m not going to go very in-depth on how I used it, but I do want to make one important note.  Groove Agent (and likely other drum samplers as well) has a “Ambience” feature that allows you to, in essence, apply some “room reverb” to the drum sound before sending it through the signal chain.  Though I don’t modify a lot of the settings in Groove Agent itself, this one I pay close attention to.  Sometimes its “natural reverb” can be an awesome addition; at other times, however, it’s best to leave it out due to a large amount of compression or other processing in the signal chain.  I used about 1/4 strength ambience for the kick to strengthen the high-end “snap” without compromising the deepness of the sound.

Now for the plugins:

  1. EQ (pre-compression)
    Kick pre-EQ
    Pre-compression EQ has a very specific purpose: to accentuate the frequency bands that should be preserved when “smashing” the sound with compression.  Often, the adjustments made here can be relatively minor.  For the kick, I boost the important frequencies slightly (100 for the “thump”, 3k for the “snap”) and cut out what’s unnecessary.  32Hz and below is very rarely useful, but since it is such a low frequency, it sucks a lot of energy in the mix, and, thus, should be cut out before compression is applied so that it doesn’t dampen the amount of volume that the rest of the frequencies have access to.
  2. Compressor
    Kick Compressor
    The main things I want to highlight in the Compressor are the attack and release.  One of the essential elements of the kick is the ”snap”—or “transient”—when the drumhead is hit.  By increasing the attack, we allow the transient to be louder without bringing up the volume of the whole sound.  I set the ratio at a medium-high level, so that the compressor works hard when it is applied.  However, I’ve kept a high release value and threshold so that compression is not applied to the decay of the kick sound.  This emphasizes the transient, which is what we want from the kick drum in a busy rock mix.
  3. Limiter
    Kick limiter
    The compressor boosts the kick volume a great deal—so much that it would clip in the mix.  Decreasing the volume technically fixed the issue, but took away from the strength of the kick sound.  As a result, I kept the compressor output high, but applied a limiter to “smooth out” the hits and keep them from clipping so harshly.
  4. EQ (post-compression)
    Kick EQ 2
    Kick EQ 1
    At this point, I de-emphasize frequencies that aren’t essential to the kick sound and give a slight boost to the kick high-end.  I do this with two copies of the same EQ plug-in in sequence, but it would be easy to merge them into one.  Note how I’m cutting frequencies far more than I’m boosting them.  That’s on purpose, and leads to an important EQ point: 
    Always cut unimportant frequencies before you boost important ones, especially after you’ve done a lot of compression and/or processing. 
    When you boost, you run the risk of trying to push the volume above the volume limits of the track, leading to clipping.  When you cut, you don’t have this issue, and if the track ends up sounding quiet, you can just increase the volume.  Since EQ boosts also boost the volume, plugin presets tend to boost—a lot.  This can make the plugin sound more loud and energetic when the user (or a potential customer) is flipping through them, but when you are mixing a full song, boosting before cutting can cause some serious mixing issues.
    You have been warned…

SNARE

Snare Channel Strip

There are actually multiple snare tracks in Traps—in addition to my regular snare setting, I added a “roomy snare” for the first verse so that it would have more “body” in the mix when the instrumentation was more sparse.  The main way I did this was simply by increasing the “Ambience” setting in the Groove Agent plugin.  The “Ambience” setting for the regular snare drum is at 0; in the busy parts of the mix, the extra “body” given by the Ambience feature just comes out muddy. 

At points in “Traps”, especially in the last chorus, there’s two snare hits at the same time.  I noticed that when I did the double hit on one instrument track, the snare sounds cancelled each other out.  This is due to an effect called “phase cancellation”, and, without going into detail (you can easily find explanations via Google if you’re curious), can easily be solved by a function called phase inversion.

I used phase inversion by splitting the double-hit snare notes into two separate tracks.  On one track, I apply the “Gain” plugin, which is simply the Logic utility plugin that includes a “Invert Phase” toggle button.  I then merged the tracks by sending them both into the same bus for processing.

I also applied EQ to each track before sending.  Again, this is a special-purpose EQ that compensates for the fact that there’s a little too much around 16.5 kHz in each drum sample, leading to a nasty clipping sound when you have two drum hit samples play at (or near) the same time.

Once the two snare samples are sent to the same bus, they both go through the same signal chain:

  1. Multiband compressor
    Snare Multiband Compressor
    Whereas a compressor brings down the volume of the entire track when it exceeds the threshold volume, a multiband compressor brings down the volume a a frequency band in a track when that band exceeds the threshold volume.  This makes a multiband compressor incredibly useful for instruments that have several important frequency bands that have to be fine-tuned—like the snare.  The snare not only has a low-frequency “thump” near 200 Hz, but it also has a “snap” around 1k-1.5k, a “rattle” (the good kind) in the 4k-6k range, and “air” in the 8k-20k range.  The multiband compressor allows us to maximize the volume of these different frequencies without them “stepping on” each other.
    To be honest, I did a lot of the multiband compressor setup by ear and trial-and-error—I pulled up a good rock track that had some snare playing on its own (The Wedding’s song “Renew”, if you were curious), and adjusted the threshold on each band until I could get the sound I wanted.
  2. Reverb (Space Designer)
    Snare Reverb
    Not all reverb plugins are made equal.  Some plugins fully generate all aspects of the reverb.  These plugins are pretty standard, but they give you a pretty artificial-sounding reverb sound.  Other plugins use an “impulse sample”—a recorded snap or other quick sound in a room—and then extrapolate the reverberations and decay of that sound file onto the track in your project.  This reverb method is called “impulse response”, and if you have (or can find) a reverb plugin that uses it, you are at a significant advantage.  Take it from someone who has used both—impulse-response reverb is worth the hassle of finding and implementing into your DAW.
    Logic has its own impulse-response plugin called Space Designer, with 100+ custom-recorded samples (and accompanying presets) for rooms and chambers of all different shapes and sizes.  In fact, the presets are so amazing that I have actually changed next to nothing in them besides the wet/dry output (on the right, labelled as “Rev” and “Dry”).
  3. EQ
    Snare EQ
    This EQ has one purpose—to bring down the 500Hz range just a touch.  500Hz is a tricky range to deal with, because nearly every instrument includes sound in that range.  As a result, to prevent the mix from being overwhelmed by that range, almost every track needs a little bit of a cut in that range.

TOMS
Toms Channel Strip 

You’ll notice the toms go to “Bus 26”—this is the same “blank” bus as the kick—so it’s the same as going to the output.

Since I like a really “boomy” toms sound, I included half-strength “Ambience” in the toms track from the get-go.

The other plugins:

  1. EQ
    Toms EQ
    You’ll notice that I’ve really emphasized the low-end—from 30Hz all the way to 150—as well as the high-end between 2k and 5k.  These are the active frequency regions of a whole bunch of other instruments—kick, bass, snare, and voice, in particular—however, since the toms serve as accents in the song and don’t often play simultaneously with the snare, I’m okay with the toms “stepping on” the other instruments just a touch when they come in.
    You may also notice that there are a whole lot of boosts in this EQ and very few cuts—this was a bad idea but I managed to get away with it because I haven’t done any compression on the track yet.  As I am working on the new album and going back to these signal chains, I’m adjusting and fixing things I didn’t quite get right the first time—as of now I’m adding this to the list! 
  2. Compressor
    Toms Compressor
    This is a relatively mild application of compression, intended to boost the volume of the toms just a touch.  Both the attack and ratio are low, so the compressor comes into effect quickly but does not dramatically affect the sound.  I’ve kept the release low so that the compressor does not “mask” the transients in tom rolls.  I put the threshold at a medium level so the the transient and some—but not all—of the ambient reverberations are processed.
  3. Reverb (Space Designer)
    Toms Reverb
    For the reverb, I used a very “noisy” tom room impulse (compare the image of the impluse audio sample here with the one for the snare to see the difference).

CYMBALS
Cymbal Channel Strip 

If you listen to cymbals during the chorus of a typical modern rock song, you’ll notice that the individual cymbal hits are not incredibly distinct—they meld into a “wash” of high-frequency energy.  Unfortunately, software instrument cymbal samples (including Groove Agent) can sound the exact opposite out-of-the-box, with each cymbal hit oddly and irritatingly clear-sounding, as if the drummer’s using a different cymbal for every hit.  To create the “wash” sound, I apply some serious compression to the individual cymbals, send them all to a bus, and then apply another, less powerful compression to blend the sounds together.

I noticed that the cymbal volumes were not very well balanced in Groove Agent, so I manually adjusted the volume of each cymbal before sending it to the bus to try to make them sound more or less “equal” in terms of volume.

Before the bus, we have the individual cymbal plugins.  For all of these, I started with half-strength Ambience:

  1. EQ (pre-compression)
    Cymbal Pre-Compression EQ
    This is a pretty straightforward EQ plugin—the low frequencies aren’t important, so I’m taking them out before applying compression.  I also applied a cut around 10kHz to keep the compressed sound from “hissing” and sounding too harsh.
  2. Compressor (UAD 1176)
    Cymbal UAD (Compressor)
    This is a special compressor that gives a better sound than the built-in Logic compressor, especially when applied heavily.  There are hardware limitations to how many I can use at once, and I can’t put them in buses, so I use the plug-in judiciously.
    The key to reading this compressor setting is that nearly every knob is backwards from its Logic counterpart.  Turning up the “Input” knob is analagous to bringing down the Threshold in the Logic Compressor.  Similarly, turning the “Attack” and “Release” knobs to the right turns them down, whereas doing the same in Logic turns them up.  Thus, in this plugin setting, I have a large attack, small release, and low threshold.  This means that I’m heavily pumping the sound through relatively mild compression.  This allows the output to have strong compression without either wiping out the transients completely or sound “smashed” with compression.
  3. EQ (post-compression)
    Cymbal Post-Compression EQ
    This is another simple EQ setting that brings up the mid- and high-frequency bands to accentuate the “body” and “sizzle” of the cymbals.  Since we just did compression, this would be best accomplished by cutting a little bit of every frequency except for the mids and highs rather than boosting the mids and highs. 

Once all the cymbals are in the bus, we have one plugin:

  1. Compressor
    Cymbal Bus Compressor
    Note the incredibly low threshold and medium-length attack on this setting.  Since we’ve somewhat normalized the volume of the individual cymbals already, we are now just “blending” the different cymbal sounds, while leaving space for the small amount of transient that we’ve let through in the individual compressors.

HI-HAT

Hi-Hat Channel Strip 

The hi-hat is a really important rhythmic element and needs to be treated differently from the cymbals.  Though there should be a little bit of blending, the rhythmic hits of the hi-hat need to remain clear and distinct.  As a result, I’ve separated it from the cymbals track and adjusted the signal chain a bit.  I started with half-strength Ambience and then applied several plug-ins:

  1. EQ (pre-compression)
    Hi-Hat Pre-Compression EQ
    The major difference between this plug-in setting and the analogous cymbal setting is that I do not have the 10k cut—since I am not smashing the hi-hat with compression as much as I was the cymbals, I do not have to adjust for high-frequency overload.
  2. Compressor
    Hi-Hat Compressor
    With the compressor, I want to strike a balance between preserving the full strength of each transient (as with the kick) and washing out all the transients (as with the cymbals).  Thus, I am using a long attack for the transients, while also applying a low threshold, long release, and high ratio for the wash.
  3. EQ (post-compression)
    Hi-Hat Post-Compression EQ
    Again, this EQ is very similar to the one I used for the cymbals, with the distinction that I am not boosting the mid-range frequencies. 
  4. Reverb (Space Designer)
    Hi-Hat Reverb
    With the reverb for the hi-hat, I want to add a bit more “body” without compromising the rhythmic clarity of the hits.  As a result, I chose a relatively dry impulse.