Low and Low Mid Buildup in Mixing

One trend we all seem to notice in mixes is that to get things to sound the way we hear them in our minds, we often end up adding top end, and or taking out low end, carving spots in the low mids, finding things to accentuate in the high mids, getting instruments focused to their midrange, etc particularly in dense mixes. Not necessarily a "lot," but regardless it seems we always have to do it. Very rarely can you just put up a session flat and have it sound almost finished.

So WHY do things cloud up in the low end? I mean obviously a bit part of it starts with arrangement, how things are played, instrument and amp choices, particular settings on these, etc. Is it related to the fact that while recording we often make everything sound big and full? You know "hit the kick drum" and we get levels and say "yeah, sounds like a kick," but in the mix it's not bright enough, and so on?

Is it that a lot of "homebrew" recording engineers are using gear that is often muddy and unclear in the mids and highs? I remember the first time I heard an A/B between a rack of real 1272s and a rack of newer API 512s. The vintage 1272s were SO much brighter and clearer than the APIs. Not that this is a bad thing whatsoever, just a different flavor.

Is it that many inexperienced engineers are recording in quite muddy sounding rooms in the first place? Even in mixes I get that are done by talented engineers, I still have to carve space.

Is it that electronics and recording technology in general can't process sound the same way that our ears do? Our ears seem to have the amazing ability to "make stuff sound better" when we can see it, experience it, etc. McGurk Effect, Coctail Party effect, any other scientific explanations will tell you that we are highly influenced by our eyes, when, if we were actually close our eyes while listening to a band at a concert (and I never do this!), it may not sound that great in comparison to the record or whatever.

The only real justifications for tracking things with big full low ends that I can find are:

1. Isolation. Micing things close with cardioid mics unfortunately gives us proximity effect

2. Getting what the client wants out of their sound - they hear it through the monitors and want it to sound huge. Make them happy, then it sucks in the mix.

3. Being able to bring certain instruments more full range at some sections than at others (for example, acoustic guitar intro, full band starting at the chorus - acoustic can easily be filtered for the rest of the song).

Other than those three though, it absolutely drives me up the walls. I feel like on the next project that I record , I'm going to double mic every close mic'ed source with a far mic. Let them hear the close mic so they can say : "dood yeah that is my TONE so fat and analog and huge and warm...but also super clean and digital and detailed and crisp" but then...secretly...my other mic is actually picking up the real sound.

I am quite convinced that since the beginning, every instrument is designed to function as a full range solo instrument. This is why a mix of acoustic guitar and vocal needs much less mixing work provided that the stuff is recorded well. When you get a typical rock track it's like trying to fit twenty solo instruments on sixty tracks down to a left and right. No wonder people have such a hard time learning to mix... It's totally counter intuitive to the way we listen to our instruments in real space. Live situations often have FAR more low end than recorded material. And it's totally valid for that application.

This brings up another interesting thought...

If you track something with low end and then roll it off, you may be reaping some of the benefits of the harmonic content naturally associated with a "big sounding" source. We can potentially all agree that in general a fender Bass through an ampeg sounds pretty great. Sounds great in the room, everyone's happy, so theoretically the mic choice and placement (eg. Brighter mic than we may usually use on a bass cab) might more effectively capture the source rather than recording with a big sounding mic and then rolling it off...

I'm no acoustician but I assume the result would be much different if you recorded a thin sounding bass through a thin sounding cab with a mic like a fet 47. The harmonics created in the mids may not be there since we've neutered our bottom end. It would probably actually sound worse. Plus the client would be completely in the dark in terms of getting "their tone." I'm a musician too like many of you, so I totally would hate a recording engineer making me completely falsify "MY SOUND" in the live room. In the mix, it obviously has to fit, but I'd be put off (even knowing what i know) if he was like "hey screw your 2x12 let's use this 1x6 cab to fit in the mix"

Plus, tiny sound is interpreted as tiny in a room mic, even if the close mic fits in the mix... Room mic would sound terrible.

Mic placement vs mic choice vs tweaking the source...

I guess it's my assumption that the source should be tweaked until it sounds good in the room, not neutered so to fit in the track as I previously joked... I think in practice having a big sounding source in the room is not always a bad thing... Makes the client happy and is of course the sound they are used to hearing in their own spaces. Now to capture it.

This is where the real art or engineering comes into play I guess. The right mic and placement is much more important than EQ obviously but the low end is a great example of why. It's proof. It's probably the same reason why we often start with overheads or rooms and just fill in... The overheads rarely have an overpowering low end which helps us out in the long run.

As far as mixing goes, checking on reference monitors and checking reference mixes when level matched is a GREAT way to see if you're in the ballpark. Low end and low mids WILL make or break your mix. Period.

A sidebar about low end -

I generally find that there's not much going on below 100hz that is anything but kick and bass. Maybe  a little floor tom ,but that's it. Reverbs have HPFs, vocals and guitars and pianos have HPFs, everything gets a highpass. Most things can stand a filter pretty high - some things up to 300 or 400hz! I generally find myself putting a HPF on kick and bass at 30-50hz, depending. Usually just to get rid of sub clutter. Guitars are generally around 100, vocals are generally 120, keys really vary depending on the role they play in the track. Pads can sometimes stand a filter up to 300 if they're supposed to be airy. Backing vocals usually get up to 150 or so, again, depending on their role.

Remember that mic distance also will affect the low end of a source, as well as mic polar pattern. Using a mic just 1" away from an amp sounds a lot different than 5" away from the amp. Proximity effect can really add up in the mix and can start to sound bad.

THE most common recording mistake I hear in tracks I get from novice engineers is low end mud. Everything is muddy. Too much lows and low mids on everything. I attribute that to the things above - proximity effect (placing cardioid mics too close to the source), sub-par acoustic environments (causing buildup of muddy frequencies), and cheap gear that is unclear in the midrange and top end.


Think about it!