By Rob Stewart - JustMastering.com - Last updated August 7, 2017
- The midrange of your mix is critical, because that is where most of the action is
- Getting it right starts at the recording stage and it can be made better or worse during mixing and mastering
This first installment focuses on where midrange issues can develop, and what you can do to avoid them.
What is the midrange, and why is it important?
Definitions of what the midrange of frequencies is will differ slightly depending upon who you ask. I define the midrange as the range between 200Hz and 5kHz which covers the entire critical range of the human voice (300Hz to 3.4kHz) plus a bit more.
The midrange of your mix is a powerful zone, because our hearing has evolved to be most sensitive to the midrange, particularly the upper mids. Too much midrange energy in your mix can make it sound too hard, too boxy, too loud or too edgy. Too little can make it sound dull, scooped or soft. Getting the mids right is critical to your mix, and midrange issues cannot always be fixed at the mastering stage. Here are some common places where the midrange can get compromised.
During the recording process
- The combination of the instrument, the microphone and the room can make or break your midrange
- Monitor and adjust the combination of instrument, room, microphone and placement to achieve the best midrange tone
Decisions on the musical instrument, its placement in the room, and the microphone(s) you choose to capture it will all start the midrange on a path. For example, if your room is heavily treated with absorption, whatever you record in that room could sound dull. This can happen when the absorption is only effective on higher frequencies which can happen if the panels are too thin. The lower mid and bass frequencies will therefore be stronger than the upper midrange. If you record in a small untreated room, it will most likely sound boxy. If you record outdoors away from any structures that would reflect midrange back to you, the lower midrange sounds much thinner.
Microphone choice makes a difference because directional microphones have a pronounced proximity effect, meaning that the bass and lower midrange is much louder relative to everything else when used at close range. A unidirectional microphone is often necessary to help reduce sounds from behind it. In some situations a unidirectional microphone can sound dull and cloudy because of bass and low-midrange build up in a room. This is because most unidirectional microphones are the most directional in the upper midrange, and they are less directional at lower frequencies. This means that a unidirectional microphone can still hear what's happening behind it, but mostly in the bass and low mids. This low-end energy gets blended in with whatever it captures from the front and the result is bass and low mids buildup. It is best to monitor for this when recording, and adjust as necessary. If the situation allows, using an omnidirectional microphone will allow you to capture a more open sound because it captures sound more evenly from all angles. The risk there is that you can end up capturing a lot of sound that you don't need or want. Adjust for this by bringing the mic closer to what you are trying to capture.
Room acoustics are often underappreciated until you have a chance to experience what a professionally treated space sounds like. When a room has been engineered to sound a certain way, fit for a purpose, it makes a huge difference. If you have ever been to a performance in a well-designed music hall with finely tuned acoustics, you may recall how easy it is to hear the performers - even when they are not performing. It can be easy to hear conversations and foot falls from a great distance. The reverberant quality of the performance space enhances your experience because the sound you hear "blooms" in a musical way. In contrast, an untreated or poorly treated room can have the opposite effect - sounding too dry (dead), boxy, or boomy which will make the production, mixing and mastering stages much more challenging.
Paying attention to the midrange at the recording stage will pay off during production. Imagine recording a muffled sounding instrument in a dull and dry sounding recording space, using a microphone that has a pronounced proximity effect. The recording will be very dull, and you will need to process it heavily in the mix to get it to sound "right". On the flip side, imagine recording a bright sounding instrument in a lively and bright sounding room, with a very bright sounding microphone. Now, your recording could be very edgy, perhaps tinny or harsh, again requiring a lot of treatment in the mix to get it to sound "right". By considering the mix of instrument, room, microphone and microphone technique, you can capture a balanced tone that will sound clear and natural, requiring less processing at the mix stage.
During the production and mixing process
- Arrangement, mix density, use of EQ and compression can allmake or break your midrange
- Keep arrangements wide open (avoid excessive layering)
- Use EQ sparingly, and use broad-brush (wide bandwidth) adjustments as opposed to narrow adjustments
- Use compression sparingly
- Avoid using one process to correct for midrange problems created by another
Arrangement and production is a fun process because you are building the song. Assembling the rhythm section and layering instruments is exciting and it can quickly become addictive. Layering can make a song sound big, and musical, but too much of it can make a mix sound busy or crowded. Most music happens in the midrange but it's all about balance. If we create too many layers in our mix, we can quickly have too much energy in the midrange, leaving not enough in the bottom and top end. This will create a very forward or harsh sound that could be tiring for your listeners. My advice: Avoid excessive layering in your production, and instead aim for an open and balanced arrangement.
Modern equalizers offer us a lot of control, but when we use them too much, or for the wrong reasons, we can compromise both the midrange tones and the performance dynamics. It is tempting to make surgical adjustments to the sound simply because we can, but that can create other problems. Here is an example. Middle C is roughly 260Hz, one octave up from that is 520Hz, and another octave up from that is 1040Hz. Imagine you are equalizing a vocal that spans three octaves starting at middle C. If you set your EQ to 1 octave bandwidth, centered at 800Hz and you boost by 3dB, you are effectively doubling the energy at 800Hz with a steep fall off towards 600Hz and 2kHz. By using this setting you are leaving the lowest octave of the vocal almost completely unprocessed, so as the singer moves from Middle C up the scale, the dynamics of their performance will change because of how the EQ was set. This may be desirable in some situations but in many cases, a wider bandwidth adjustment that covers more of the range will sound more natural. My advice: Use EQ sparingly, and when you do, use "broad-brush", multi-octave adjustments to avoid unintended peaks in the midrange.
Compression helps beef up the midrange which helps add a sense of fullness to a mix. Compression also tricks us into thinking that something sounds louder, because it allows us to boost the gain. When we compress too much, or we compress too often throughout a mix, the mix starts to sound confined because everything in the mix has been flattened by compression. When everything in the mix is at a relatively high and stable gain level, the mix lacks contrast. Compression also raises the noise levels inside your mix which contributes to the congestion. By using the makeup gain on the compressor, you also raise everything in the background. This boosts the noise(s), the reverb decay of the space, and the sustain of every note. Multiply this across several tracks, and you end up with a lot of congestion. Suddenly your mix is struggling to stay above layers of unwanted noise and sound. My advice: Compress only when you need to. Avoid compressing for the sake of "glue". Instead, if your mix sounds "unglued" listen carefully for the reasons why (is it the arrangement, the performance, or the mix?).
EQ and compression help us solve problems, but we can easily fall into a trap of using one tool to fix the problems of the other. For example, compress too much and suddenly the midrange sounds a little tubby. You can then decide to either reduce the amount of compression, or use an EQ to boost the energy in the top end. If you chose to EQ, the result is a track that has compromised dynamics, compromised tone, and even higher noise levels because of the added EQ boost that was needed to address the damage done by the compressor. My advice: If a process has compromised your sound, avoid using another process to try to correct for the problems created by the first. Reduce or reverse the offending process first.
This last concept applies at the earliest stages of the recording process. For example, if you are capturing an instrument and it sounds dull over the monitors while you are recording it, EQ'ing it later will add noise. Instead, change the position of the microphone, or even use a different microphone to see if that will improve the result so that you need less processing later.
Midrange quality and clarity can be supported, enhanced, changed or damaged at every stage of the production process. You can achieve the best sound by getting closer to "ideal tone" and "ideal dynamics" at the early recording and production stages, allowing you to use less processing in the production and mixing stages.
In Part 2, I will discuss the different midrange zones, and how they impact the sound quality of your mix.