Recording - March 2013 - 42

I stuck an eq plug-in on the top snare mic and selected a band-reject filter with a very narrow Q. I then
swept the frequency control up and down until the
“boing” mostly went away. The narrow Q setting let
me do this without noticeably degrading the sound on
this track. See Figure 1 for how I did this in Pro Tools.
“Q” stands for “quality” and is the center frequency of the eq band divided by the bandwidth of that
band in Hertz. As the Q value number goes up, the
bandwidth gets more narrow, and as the Q value
number goes down, the bandwidth gets wider.
Q tells you the narrowness of your eq band with a number
that is based on musical octaves, so it stays the same regardless
of your eq band’s center frequency. “Q” is sometimes incorrectly referred to as “bandwidth”, but a direct bandwidth control
would not be very useful.

top snare mic because the drum head moves away
from that mic as it moves toward the bottom mic.
Reversing the polarity of the top mic lets both mics
push the speaker cone towards you when the drum
gets whacked. Polarity was reversed on all tracks
where the mic was above the drum or cymbal, but
not on the bottom snare or kick mics.
Speaking of kick, we also had two mics on that
drum, a Shure Beta 52 inside the drum and an MXL
Cube condenser about a foot away. These two mics
were time-aligned and routed to a mono kick aux track. Faders
were adjusted and the sound was good enough that I did not
feel the need to equalize the individual mics. Later on I would
equalize the kick aux and the snare aux, but we’re not quite
ready to do that yet (that’ll be in Part 3!). To finish up the routing, all the mics on the drum set were routed to a stereo aux

As an example, Figure 2 shows two eq bands, each with a Q
of 1.0 but very different bandwidths. The yellow band has a center frequency of 200 Hz and a bandwidth of 200 Hertz, from
about 150 Hz to about 350 Hz. (We consider the bandwidth to

which I named “Drums Close”. This aux track was routed to a
main “DRUMS” aux, along with the distant room mics, so that I
could time-align all the close mics to the distant mics and process
these two auxes separately. (We showed that in Part 1.)

Always time-align the drum mics to the overheads, and use equalization to
attenuate objectionable frequencies before boosting desirable frequencies.
be the region wherein there is a boost or cut of 3 dB or more.)
The blue band has a center frequency of 5 kHz and a bandwidth
of 5 kHz, from about 3 kHz to about 8 kHz. Because these two
curves look the same on our exponential frequency chart, it is
much more useful to have a Q control that stays at 1.0 at these
two center frequencies than it would be to have a bandwidth control that you would have to change from 200 to 5000 to get the
same effect.
On my ride cymbal and hi-hat tracks I used highpass (lowcut) filters to eliminate all frequencies below those produced by the cymbals. I also felt that the overhead mics were a bit too harsh, so I
ended up cutting a few dB around 5 kHz to smooth them out a bit.
Routing
I also had a mic on the bottom of the snare to add the crispy
high end that you don’t get from the top mic. Both of these mics
were routed to a mono aux track so I could blend the thump of
the top mic with the crispy crack of the bottom mic. In last
month’s article I also explained how I reversed the polarity of the
42

RECORDING March 2013

Ringing
The next issue to address was the ringing resonance of the
rack toms. Despite that really rad and righteous alliteration, the
ringing is a bad thing: really rank. The heads on the toms
vibrate in sympathy as their brother drums are mercilessly battered. This results in a steady drone of muck that spreads a blanket of non-clarity over your whole mix. To clean this up I inserted expander plug-ins on each tom track. Figure 3 is a screen
shot of this plug-in.
The square graph on this plug-in shows you the amplitude
(audio volume level) of the input to the plug-in on the horizontal
axis, vs. the amplitude of the output on the vertical axis. In the
screen shot, the input amplitude is –20 dB, and so is the output
amplitude. The threshold is set to –30 dB. When the input amplitude is greater than the threshold the plug-in does nothing. But
when the input amplitude is less than the threshold, the
expander applies gain reduction, making the signal quieter.
Now look at Figure 4. Here, the input signal amplitude is –36 dB,
which is 6 dB below the threshold. The expander’s ratio control is

Recording - March 2013

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