
Recording Vocals (pt I)
Ask people what the most important element in a recording is, and most will agree that it's the vocals. And no
matter how good your music is, a sub-standard vocal can kill it quicker than Prince Naseem can duck n' dive.
Whilst they certainly help, top-quality microphones and state-of-the-art recording equipment are not a prerequisite
for a great vocal recording. Excellent results can be obtained using more modest equipment. Nor do you need the
voice and talent of Frank Sinatra or Aretha Franklin - with a little patience and the use of a few simple techniques,
any singer can end up with their best possible recorded vocal.
Over the next few issues of The Mix this series will cover the basics of recording vocals, with techniques, hints
and tips to help get the best possible performance recorded with the best possible sound. So let's start from the
beginning - what equipment to use, and how to set it up.
Microphones
Both condenser and dynamic microphones can be used to record vocals. Generally in professional studios, largediaphragm
condensers are used, as they have a refined sound with a wide dynamic range and extended
frequency response. Many excellent vocals, however, have been recorded on commonly available dynamics like
the Shure SM58.
Choice of mic is down to what you have available, but in a situation where you have several different models,
make your choice based on which mic suits the singer's voice for a particular song. Many engineers and
producers will put up several mics initially to check which one sounds best.
Having chosen a microphone, it's preferable to mount it on a stand. Most mics come supplied with a mount, and
the more expensive ones will have a suspended cradle mounting to isolate the microphone from shock and
vibration.
It is possible to record vocals using a hand-held mic like an SM58 but, in terms of the sound being recorded, there
are several reasons why this is not ideal. Firstly, there is handling noise to consider - the sound of the singer
moving their grip on the microphone and moving it around will be picked up. Secondly, unless the singer is very
experienced with mic technique, the mic will be held at different distances from the mouth at various times,
resulting in small changes in timbre and level. And, thirdly a hand-held mic rules out the possibility of using a pop
shield.
Now, having pointed out the drawbacks, it must be said that there will always be some singers who feel most
comfortable using a hand-held mic. In this case, recording with a hand-held is the way to go, because a relaxed
and confident singer is going to turn in a better performance than one who is uptight about having to stand still
and sing into a stand-mounted mic. A slightly less-than-perfect sound is a small price to pay for a great vocal
performance.
Arctic rolls
The next thing to consider about a microphone is its polar pattern. Many mics, especially less expensive ones,
have a fixed polar pattern, usually cardioid. Others have a switchable polar pattern, but unless you are after a
certain effect, switching it to cardioid is preferable.
Cardioid mics are the norm for recording vocals as they accept sound from directly in front and reject much of
what comes from the back and sides. This is important in the context of the room where the vocal recording is to
take place, as reflections from the walls may be picked up by the microphone, adding some of the ambient sound
of that room to the vocal sound. This would obviously be more pronounced if an omni pattern was selected on the
mic.
Now, there may be occasions where you will want to record in a particular room to pick up the sound of the room
or the reflections from, say, a window or wall in the room, if that will suit the track you are working on. But in most
cases it is probably best to record a vocal in a dead-sounding area and add any ambience at the mixing stage
using a reverb unit, because once ambience is recorded with a vocal, you are stuck with it
Some studios have acoustically-treated vocal booths, but if you have to record your vocals in a normal-sized
room, a dead area can be created by siting acoustic screens around the microphone. The DIY approach to this for
home recording is to hang curtains, duvets, blankets or something similar around the singing area.
A couple of self-assembly bedroom tidy rails from the Argos catalogue make an inexpensive and practical
framework to hang material on and construct a functional vocal booth. These can be disassembled and stored
away when they're not needed.
6" is ideal
A singer's distance from the mic can make a lot of difference to the sound recorded. A distance of 6" or so is
perhaps a good starting point, although experienced singers will work the mic by leaning into it for some passages
and moving back for louder sections.
Sing too far away from the mic and more of the room ambience will be picked up; sing closer to the mic and more
of the proximity effect comes into play. Proximity effect is a pronounced boost in low frequencies which results in
the voice sounding bassier when singing very close to the mic, and it can be successfully exploited by an
experienced vocalist.
It is best to try to keep a vocalist at a consistent distance from the mic, particularly when doing multiple takes and
where he/she has to leave the booth to listen to playbacks and then go back and sing the odd line. If the same
distance from the mic is maintained, variations in volume and timbre between takes is minimised, and dropped-in
lines will sound more natural.
Once a singer is at the optimum distance from the microphone, mark the position of their feet on the floor with
gaffa tape so that they can go back to the same position each time, and don't forget to mark the position of the mic
stand at the same time in case it is accidently moved.
The height of the microphone on its stand in relation to the singer is also a factor to take into consideration. Some
like to sing up to a mic suspended a little higher than them, but this can strain the voice if the head, neck and
shoulders are stretched up. A mic that is suspended too low is also not ideal if it causes the singer to hunch over,
although this at least puts less strain on the neck and shoulders.
An advisable starting position is to have the capsule level with the singer's mouth and then move it if necessary to
suit the singer's most comfortable stance. Having the capsule level with the singer's mouth creates its own
problems, as it is more susceptible to blasts of air, but there are methods to counter this, the most important of
which is the use of a pop shield.
A pop shield is generally put up a couple of inches in front of the mic and its basic function is to stop plosives,
which are the popping sounds from blasts of air usually produced by singing the vowels 'B' and 'P'. The pop shield
also serves to protect microphones from spit and moisture produced by the singer.
Commercially available pop shields, which usually have a gooseneck and a clamp allowing direct fixing to the mic
stand, are fairly expensive. However a home-made substitute can easily be constructed from a pair of tights
stretched over a bent wire coathanger - just remember to wash them first if they've been previously worn!
If you cannot attach the pop shield directly to the mic stand, try using a second mic stand purely as support for the
pop shield. One useful trick is to fix a pencil vertically down the centre of the pop shield, as this tends to dissipate
the energy of blasts of air before they reach the mic. If popping problems still persist, try getting the singer to sing
slightly to the side, above or below the mic. If a singer has difficulty doing this and needs to focus directly on the
mic, put up another mic that is not plugged in and site it right next to the real vocal mic. Then let the singer sing
into this dummy mic.
Whisper to a scream
Microphones have to be connected to a pre-amplifier, and there are two options available. Connection can either
be into the mic amp in a mixing desk's input channel, or into a standalone mic pre-amp. These provide a higher
quality signal path to the recording medium than that provided by the average mixing desk.
A budget mixing desk will have identical mic amps on all of its input channels and these are built to a price, so a
standalone pre-amp, relatively more expensive than one desk input channel, ought to have better quality
components and a cleaner signal path. Also, a shorter signal path to the recorder is usually provided by a
standalone pre-amp which can connect directly to it, whereas the signal through a mixing desk may have to pass
through input channel, group busses and patchbay.
Compression is near-essential to even out the performance when recording vocals. The human voice has a huge
dynamic range (from a whisper to a scream, to use the old cliché), and a compressor will 'squash' that range a
little. Don't go over the top, though; reducing the peaks by a few dB ought to be sufficient. Once compression is
recorded you can't take it off, so it's best to err on the side of caution. More compression can, of course, be added
as needed at the mixing stage.
Several of the standalone pre-amps on the market have their own compressor built in. When recording through a
desk's input channel, a compressor should be connected via the channel's insert points.
EQ can also be applied when recording vocals, perhaps to remove a bit of nasal honk from a voice, to brighten up
the sound a little, or, most usefully, to filter out some of the bottom end of the spectrum. Real low frequency
sounds, such as outside traffic rumble or the sound of the singer's feet moving on the floor can be transmitted up
the stand to the microphone, and an increase in bass due to the previously mentioned proximity effect can also be
a problem.
To get around this, switch in a high-pass or bass roll-off filter. Most mic pre-amps and desk channels, and some
mics, will have a switchable filter operating at somewhere between 75Hz and 100Hz, cutting out most of the low
end below that figure.
EQ should, however be applied with caution. Adding too much top-end boost, for example, can often exaggerate
the sibilance of the voice. It's best to record a vocal flat, but if you feel the need for EQ, use it sparingly. And while
you may be tempted to use a noise gate or downward expander to cut out noise between phrases, our advice is
not to. It's too easy to chop the end off notes and make the vocal sound unnatural.
Processing of this sort should be left to the mix stage, when time can be taken to set it up accurately.
Condenser or dynamic?
Although there are other designs, the microphones most commonly used in studios today fall into one of two
categories - condenser or dynamic. A microphone is simply a device which converts acoustic energy (sound
waves) into electrical energy, and the dynamic and the condenser each do that in their own way. This has
consequences for the sound produced, and hence the use to which each is put.
A condenser mic, also known as a capacitor mic, has a thin diaphragm that is supported around its rim at a small
distance from a thicker backplate. The theory is that the two form the two electrodes of a simple capacitor, and are
oppositely charged by the application of a polarising voltage. When the diaphragm moves in response to sound
waves, the spacing of the diaphragm and backplate (and hence the capacitance) will vary, and this is used to
generate the output voltage.
Because a voltage has to be supplied to the backplate and diaphragm, a mic of this nature needs a power supply.
This usually comes in the form of 48V phantom power supplied from the mixing desk or mic pre-amp. Condenser
mics are more difficult to manufacture than dynamics and are therefore more expensive; they are also not as
rugged and are more susceptible to changes in atmospheric conditions, so should be stored, and handled, with
care.
In use, a condenser is generally more sensitive than a dynamic and has a better transient response. It also has a
wider frequency response, so can pick up more top end than a dynamic, making it very useful for instruments like
cymbals, acoustic guitars, and vocals.
Condensers can be built with two diaphragms, and by changing the voltage of the second diaphragm in relation to
the first, the mic is capable of several different polar patterns - from omni-directional through cardioid to figure-ofeight.
Some condensers are designed with a valve in the circuitry; these do not need phantom power as they
usually come with their own power supply. Valve mics provide a different tonality than the standard condenser,
with an added warmth in the sound.
Another variation from the standard condenser design is the electret mic, which uses a permanently charged
electret material to charge the capsule. These mics are usually cheaper than condensers and can often be run
from a battery if you do not have a phantom power source.
Dynamic mics work because of the electromagnetic interaction between the field of a magnet and a moving coil
conductor. A coil of wire, surrounded by magnets, is fixed to the back of the diaphragm, the motion of which
results in the coil cutting through the magnetic field, inducing an electric current in the coil.
Unlike condensers, dynamic mics do not require any power supply. They are more robust, and can cope with high
sound pressure levels.
Because dynamics are pressure- operated, their polar response can only be either omnidirectional or cardioid,
and most handheld dynamic vocal mics are cardioids. Dynamics are also limited in their high frequency response,
some having an upper limit of 16k (a good capacitor will go up to 20k).
Mics designed for stage use will often have a bass end roll-off built in to counteract the proximity effect, and many
have a presence peak built into their frequency response somewhere up around 5k. This is designed to help
vocals cut through a mix. Some very well-known rock singers rcord their vocals with dynamic mics for that
particular punchy sound.
Microphone Polar Patterns
There are four basic options when considering a mic's polar pattern:
A cardioid (or unidirectional) mic is so named because of its heart-shaped response. It will pick up sound mostly
from the front. Dynamic cardioid microphones are popular for vocals because of their off-axis exclusion, and
robustness, but condenser cardioids are much better for the studio vocalist.
A figure-of-eight microphone picks up sound from both front and rear of the diaphragm, but because the opposite
sides are out of phase, side-on sources get cancelled out. Figure-of-eight microphones have the potential for very
accurate recordings.
A circle is the polar response of an 'ideal'
omni-directional microphone. In practice, the response favours the 'open' side of the capsule at higher
frequencies, so off-axis sources can be dull. Omni mics are particularly resistant to wind and
handling noise.
A hypercardioid microphone mixes the cardioid and figure-of-eight patterns to produce a 'thin' cardioid with an
out-of-phase area at the rear. Because of this, the hypercardioid is good for reducing the effect of reflected or offaxis
sounds, such as room reflections.
Vocal Mics
£2,000 +
Some 1950's valve vocal microphones are still in use today. The Neumann U47 and the AKG C12 are universally
regarded as classics and sell for well in excess of £3,000 on the used market. AKG now produce a reissue of the
C12, in the form of the C12 VR, M149, and the soon-to-be-released M147.
Below £2,000
The Neumann U87 and AKG C414 are the two most common vocal condensers used in studios today.
Below £1,000
Anyone wanting to buy a decent condenser under £1,000 for vocal use is spoilt for choice. AKG's SolidTube
incorporates a valve in the design. Beyer's 834 and Audio Technica's 4033 and 4050 are all respected, and many
of the eastern European imports give great results for a reasonable price. Australian-made Rode Microphones
represent excellent value for money, and AKG weigh in with several of inexpensive contenders: the C4000B,
C3000, C2000 and C1000S.
Below £100
There are loads of inexpensive dynamic mics available, but think of a dynamic vocal mic and you invariably come
up with the Shure SM58. This rugged workhorse is the industry standard hand-held stage mic, but its partner, the
SM57, will also give good recorded results.
(In part II, we look at setting up a headphone mix, and getting the best out of a singer.)