ON TRACK
RICH TOZZOLI
Optimal Low-End Mixing
With the amazing popularity of home stu-
dios, many of today’s recording projects are
done using software DAWs (Digital Audio
Workstations) such as Pro Tools, Logic,
Cubase, Live, or Reason. Of course, there
are still plenty of analog studios out there
using good old-fashioned tape and a con-
sole. Whatever you may run, it’s
important to think about your
use of equalization during that
final mix phase. Too often I see
people cranking up the EQ in
an effort to get tracks to punch
through and be heard. It’s quite
easy with a DAW to just call up
a plug-in and start boosting.
While that sometimes will work,
it often causes a problem called
masking—where tracks cannot
be clearly heard because other
tracks have taken up their fre-
quency range.
One way to start cleaning up the bottom of
your mix is to use subtractive equalization. By
soloing up each track, you can get a better
idea of which instruments need some reduction. One effective technique that I use is
calling up a plug-in on my DAW such as the
free Inspector tool from RNDigital [rndigital.
for the kick and bass to live, so they shine
through in a mix. If you notice too much
low-end coming out of your mix, gradually
add some back in until the ‘beef’ returns.
Certainly, if it’s a track without kick and
bass, you can leave more low-end in the mix
than usual.
Think of a mix as a finite amount
of lows, mids and highs that
must fit through a set of speakers, small and large. In a typical rock/pop mix, the lows will
consist of your kick and bass. In
addition to real kicks and bass,
you’ll often find synth/sample
versions blended in there as well.
I’ve found that getting the low-end correct in a mix is one of the
hardest things to do, so that will
be the focus of this column.
While there are many different
kinds of equalizers, I have found
that parametric EQs are the most
effective when pruning down a
mix. Unlike a graphic EQ, which
simply has fixed bands that can
be either cut or boosted, parametric EQs feature amplitude (the
amount of cut/boost), center frequency (the chosen numeric range)
and bandwidth, or Q (the width of
cut/boost around the center frequency). So if you need to remove
the area around 148 Hz, you can
quickly dial it up with a parametric
EQ and cut away that exact frequency range.
In addition to parametric EQs,
I use quite a bit of high- and
low-pass filtering. By engaging a
high-pass filter, you can attenuate
(cut) frequencies lower than the
selected cutoff value. This lets you
quickly remove a ‘chunk’ of low-end without dialing in the bands of
an EQ. It’s a quick and simple way
to start cutting out the excess.
Aside from making sure your monitors and
room are feeding you accurate information,
you can do yourself a favor and think about
cutting frequencies on other instruments that
use up that low-end range. The above-men-tioned kick and bass have a large portion of
their frequency information sitting from about
40 up to around 180 Hz. That range should
be cleaned up, in order to let those bottom-heavy tracks be clearly heard. But think about
how many other instruments have frequencies down there. One of the worst offenders is acoustic guitars. When recorded with
a decent microphone, there will be a large
amount of information in that 100 Hz range.
Electric guitars are also another offender, as
are synth pads, keyboards and even closely
mic’ed vocals.
org/ inspector.html]. This RTAS, VST and AU
analysis tool will display not only frequencies,
headroom and levels, but detect clipped samples (for those of you who push your mixes
into the red). Other programs such as Logic
have analysis tools built in, so take advantage
of them if you can.
Once I’ve taken a look (and listen) to the
tracks in question, I will call up a good EQ
and start cutting the trouble spots out. For
example, I will often cut and/or reduce the
low-end out of acoustic guitars up to around
150 Hz. The same can be done for those keyboard tracks and synth pads, etc. With vocals,
I will always remove anything below 100 Hz
and often up to 150 Hz. This reduction has
a cumulative effect of creating more space
Whatever technique you choose, try cleaning
up the bottom of your next mix with some
filtering or subtractive EQ. Not only will it provide more clarity to your music, it allows you
to make the overall mix louder, since there’s
now less muddy low-end clouding up the full
frequency spectrum. And of course, as long as
that guitar is cranking, it’s all good!
Rich Tozzoli
is a producer, engineer and mixer who has worked with
artists ranging from Al DiMeola to David Bowie. A life-long guitarist, he’s also the author of Pro Tools Surround
Sound Mixing and composes for such networks as
Discovery Channel, Nickelodeon and National Geographic.
