Recording - February 2016 - 36

commercial products for this nowadays) can help control room noise, especially with
higher-pitched sounds. The best solution may be a vocal booth, which isolates the performer and mic from any room noise (at reasonable levels, we're not talking about a
full drumkit 3 feet away). Commercial offerings can be pricey, but DIY solutions can
work nearly as well with a little extra research and effort.
If you do find yourself with a recorded vocal track that has problematic leakage/
background noise, there are several ways to approach it after the fact. If the noise is
buried under the voice itself and only becomes audible between words and phrases,
then you're in reasonably good shape. A noise gate will automatically reduce or eliminate the noise when the vocal pauses momentarily-technically, when the main vocal
drops below a certain level threshold, which you would set by hand. To avoid accidentally gating out any of the vocal itself, a fast attack is called for. Finally, for the gate to
do its job properly, it should be the first plug-in in the chain (the top slot).
Alternatively, you could edit the noise out, either by hand (tedious), or with the Strip
Silence function included in most DAWs. This will do the same thing as the noise gate,
but it accomplishes the task by actually cutting up the vocal regions. If you have trouble finding a threshold that works properly for the whole track with a gate, you can
automate it, or use Strip Silence and then tweak any of the cuts that require further
adjustment. Figure 1 shows a noise gate plug-in and Strip Silence in action.

Fig 2. Addressing noise/leakage under the vocal-
Audio Repair modules in iZotope's RX 5: Spectral Repair, De-Noise, and De-Hum
If the noise is audible along with the vocal, then it'll be more difficult to deal with-
but don't despair, there are still potential solutions! Specialized "audio repair" software (like iZotope's RX 5, among others-see Figure 2) offers tools to distinguish
unwanted sound/noise within a wave from the desired vocal, like De-Hum, De-Buzz,
or Spectral Repair. However, depending on the noise, these tools can often be a bit
finicky. Although this kind of processing can frequently perform miracles, the success
rate may still not be 100%, so once again it's best to stop this problem at the source
whenever possible.
Keep your distance
A number of common issues can arise at the mic itself. Not maintaining the proper
distance from the mic for a studio recording is a common mistake for those more used
to stage performance/live recording. Unlike stage mics, which are intended to be used
right up against the vocalist's lips, a studio condenser mic needs at least 6" to 12" distance to capture an open, natural vocal tone. If the vocalist is too close, a couple of
problems may result.
One is proximity effect-a large bass boost that occurs with directional mics, which
includes most studio LDCs. It can make an announcer's voice sound great (the "voice of
God" effect), but for music vocals it's usually too much, making them sound tubby and flabby.
Another issue is p-pops-technically, plosives. Some letters-notably "p"s and "b"s-
may cause the mic's diaphragm to shake, creating a loud, bassy pop-an obvious and
unacceptable flaw for any recording. With a performer or mic prone to this, it'll be
worst at closer mic distances.
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RECORDING February 2016

Both of these issues can typically be
mitigated by measuring and maintaining
proper mic distance-again, 6" to 12".
A common approach is to have the
vocalist hold up a hand between their
lips and the mic, fingers spread wide, to
eyeball an appropriate distance. This
should prevent excessive bass buildup
from proximity. P-pops, however, aren't
fully controllable with distance; see
Figure 3 for other solutions.
First, use a dedicated pop filter.
You've seen these-a thin mesh or
foam in a round frame, mounted on
the mic stand. Panty hose on a wire
hanger was often used in the olden
days, but the modern commercial ones
are more dignified. Positioning the
popscreen 6" to 12" from the mic
solves two problems: it stops pops and
sets a guide for the vocalist as to proper distance. The singer can get right
up on the screen while still maintaining proper distance from the mic itself.
If there's still a problem with p-pops
(and sometimes they may persist even
with all these precautions taken), you
could also try angling the mic just a little off-axis from the vocalist. Turn it to
the side or a little above, maybe
5-10° or so at most-not too much or
it might negatively impact your tone.
This may position the mic's diaphragm
just enough out of the direct path of the
air blasts that cause the pops.
Sometimes you may be handed a
recorded vocal with proximity and plosive issues and be expected to mix it.
The bass boost from proximity can, of
course, be EQed out, typically with a
broad bass cut or shelf starting at
around 200 Hz or so. But watch out-
at closer distances, the amount of bass
boost may be noticeably inconsistent if
the player moved around a bit. Then
an EQ remedy may require more
attention, possibly using automation,
to effectively neutralize the boost without compromising vocal tone in other
parts of the recording.
There are a couple of ways to deal
with plosives. A highpass filter could
control the bass in the p-pops, but I
find this usually thins out the overall
vocal tone too much. Editing offers a
better solution-cut the vocal region(s)
at the point of each pop, and fade in
over the pop (it should be clearly visible in the wave). This is very effective
for the occasional pop, but if there
are a lot of plosives it can be tedious
and time-consuming. For more efficient problem-solving, some software
now provides automatic removal of

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