Betteridge back again, with a step-by-step guide to the mysteries of mike technique.
Problems with home taping? Jim Betteridge mikes it better.
There's been all sorts of nonsense talked about mikes and mike technique over the years — no small amount of it by me, admittedly. It's become more like the fashion business than a science-based industry; there are so many very good mikes around today that, assuming certain basic requirements are understood and met, choosing the right model for the right job is almost entirely a matter of taste. Just like any other musical instrument, in fact. There are those who take great care to try out dozens of different models to arrive at their 'Right Sound' and there are others who see less importance in it. For instance, I was at a Men At Work concert a couple of years ago where the engineer was using exclusively Shure SM58s for everything, from bass drum to lead vocal. It sounded fine.
The important thing for home recordists is that you no longer have to pay large amounts to get a mike capable of a very acceptable all-round performance. Though the esoterics of the subject can get a little convoluted, mike technique is very important and can make all the difference to the final product. Here we take a look at what kind of mike you might like to buy and where you might like to stick it once it's yours.
The job of a microphone is to convert, or 'transduce', sound into a representative electrical signal that can be amplified and/or recorded. There are a number of ways in which this can done and thus there are a commensurate number of categories of microphone. Common transducer types include ribbon, condenser and dynamic, sometimes called moving coil. In the lower cost bracket the healthiest combination of sonic performance, durability and price is generally found in the dynamic mike, and so to keep things simple I suggest that that's what you go for. There are low cost condensers around that might offer a brighter sound, but they will tend to be less robust and if you're also considering using the same mikes for live work the dynamics are a wiser bet.
Another category for mikes is their directional response, ie how wide an angle they will pick up sound from. For most applications you will want a mike that picks up sound mostly from the direction in which you are pointing it, ie your mouth or the guitar and not from anywhere else in the room like the squeaky chair or the window past which the outside world might be noisily passing. On the other hand you don't want such a narrow angle of response that you don't dare move your head or shift in your chair during a performance for fear of going off axis. Here again there are a number of possibilities, but the most commonly used is the, what can loosely be described as, unidirectional or cardioid — because graphically the response shape looks vaguely like a heart. Common alternatives are omnidirectional giving all-round pick up, and hyper-cardioid/super-cardioid both of which have a narrower directional response for where rejection of ambient sound is particularly important.
The term 'balancing' refers to the nature of the mike's electrical connection to another piece of equipment. Although possibly a little more expensive, a balanced microphone (as opposed to an unbalanced one) will generally offer lower noise levels and be less susceptible to interference and is therefore definitely recommended. If your mixer has unbalanced inputs it will simply 'unbalance' the mike as you connect it, and no damage will be done, although the advantages of having a balanced mike will be lost. In this case it is possible to get an in-line balancing transformer to go between the mike and the mixer input which will preserve the performance of your mike. On the subject of impedance — most modern mixers will cope with a low impedance microphone and again, without going into any lengthy explanation, these are recommended for a better performance. The combination of balancing and low impedance will allow you to use long mike lead runs without loss of quality, which is very useful if you want to check out the acoustics of the bathroom for vocals, etc.
The sound of even the best acoustic instrument will be greatly affected by the acoustic of the room in which it's played. Most moderately proportioned, furnished domestic rooms will tend to have a rather boxy, probably bass-heavy sound to them and so, although it's obviously wise to experiment (more about that later), it is likely that for subtler recordings (as opposed to miking up a 100 watt guitar stack) you'll want to use reasonably close miking techniques to keep the effect of the acoustic to a minimum. Ambience will then have to be added back artificially but that is generally preferable to an inappropriate 'natural' sound. For the most part, the type of mike recommended above will exhibit what is known as the proximity effect: as the sound source gets closer to the mike the bass frequencies will be boosted. This can be a positive or negative effect depending on what it sounds like, but it's certainly something to bear in mind when close-miking.
As a general starting point, place the mike about 10" away, more or less in line with the mouth and see how it sounds. Problems with sizzling sibilants and popping 'P's and 'B's increase as you get nearer to the mike, and so if you're having problems in those areas, try moving back a little and singing slightly off axis or across the mike rather than straight into it. Pop shields will generally take out pops but sometimes at the expense of high frequencies and hence clarity and definition. A popular and reasonably transparent method is to use the leg of a pair of tights stretched over a wire coat hanger in the shape of an 'O'. The hanger is then taped to a mike stand so that it can be easily placed between the singer and the mike. You can also try using the speaker cover in place of the stocking and coat hanger, and it used to be common practice to wrap Auratone covers around the mike with Sellotape. Anything like that will work, and you just have to listen to decide whether it has too adverse an affect on the sound or not. Steve Parker, whose clients include artists from The Stones to Aretha Franklin, had an interesting alternative idea for losing pops:
"I learnt this many years ago from a well known American engineer call Bones Howe. He used to tape a pencil across the face of the mike to help break up the direct impact of the wave front. It won't stop really bad popping, but it certainly helps and doesn't affect the rest of the sound."
Sibilance can be trickier to effectively counteract, although again singing a little off axis can help. You can try rewriting the lyrics to cut out all 'S's, but you may get into copyright problems, and if you ask the singer to try and kerb it, you can end up with a lithpy vocal. De-essers can help mitigate, but they do have their side effects and especially with low cost units it is generally thought better to put up with a little sizzling rather than screwing up the overall sound. The same goes for trying to correct it with excessive eq. As with other instruments, a little compression can greatly improve a vocal sound, but it will tend to increase sibilance and pops, so sometimes it's compromise.
If you're using a de-esser in conjunction with a compressor, you have to be careful, as Townhouse Studios engineer, Alan Douglas, explained:
"It is a bit of a Catch 22 situation because although compression can bring up sibilance thereby giving the de-esser more to do, a compressor will also tend to bring out any artifacts produced by the de-esser and that tends to be more intrusive. So I always compress before I de-ess."
The proximity effect mentioned above is commonly used to create a more intimate vocal sound during a performance — as you get closer to the mike the sound becomes warmer and more intimate, and it's normal to back off a little as the voice gets louder and more aggressive. Again there's no right and wrong with this, it's just something to consider and experiment with.
If you're intending to buy two or more mikes it's an idea to get at least two the same so that you can set up an equal stereo pair. This technique is commonly used in classical music recordings to capture the natural acoustic stereo picture on a stereo pair of tracks. If you're working with a four-track format this may be a luxury you can't afford, but for singer/songwriters working with an acoustic piano, bass and vocals, a good piano sound is important, and if you have eight or more tracks, you may want to experiment with creating space acoustically with other instruments or ensembles. The 'coincident pair' technique involves using two mikes to create an 'X' configuration to approximate the reception of sound at our ears. The angle of the 'X' is generally between 90° and 120°. A wider more defined stereo picture can be achieved with a spaced pair, but it isn't generally such a natural sound, and too great a gap can result in a hole in the middle. Listen to both and decide.
With upright pianos (I assume few of you have grands) I have got some great sounds by removing the instrument's front cover and using a coincident pair (not always matched so don't worry too much about that) positioned fairly close (about 6" to 8") to the strings at the point the hammers hit. This will result in a bright, open sound with a natural stereo image. Unless you are working with a high quality grand, it is difficult to get that big bright sound without really laying into the keys hard. Thus it is advisable to keep your piano parts simple and play them very positively and as firmly as the old Joanna's action can take. You can also try miking up the sound board from behind and from underneath, although I have personally found these less effective for straightforward acoustic piano sounds.
With an acoustic guitar, the nearer the mike is to the bridge, the brighter the sound tends to be and, conversely, the nearer the sound hole results in a fuller timbre. Directing the mike downwards towards the higher pitched strings and effecting a slight roll around 200Hz will help prevent boominess. On the other hand Tony Visconti, who has produced artists from Bowie to Thin Lizzy, has this to say:
"I like to point the mike right at the end of the fret board; the sound hole makes the sound too resonant and miking the body makes it too wooden. The end of the fretboard is a good balance."
The saxophone differs from the clarinet in that it is a 'closed system', and thus all of its sound is projected from its bell, whereas with the clarinet the lower component of its sound comes from its finger holes. When miking up a sax, then, the only question is whether you want to hear the key clatter or not, and thus whether you point the mike downwards at the bell or upwards towards the keys. With a clarinet, the mike can be pointed directly at the band where the bell is attached to the body for a balanced sound. Brass instruments are also closed systems and thus the bell is the focus of the mike. With sax and brass, levels can get high enough to overload low cost dynamics at close range, and so it's wise to give a space of at least a couple of feet — this will tend to produce the best sound anyway.
The flute sends most of its sound out in two directions and so it is good to have one mike facing the lips of the player with a second mike pointing roughly toward the other end of the instrument, inline with it.
The assumption here is that most drum tracks will be done with drum machines although some overdubs will take place. Again it's all about using your ears, but a deeper snare sound can be arrived at by substantially loosening the top skin (sometimes beyond what a normal drummer would like for performance). Snares tend to be set off rattling at the slightest sound and so if you use a bottom mike in addition to the top mike to pick up the sizzle of the snares, it is a good idea to gate it using the output of the top mike, thus preventing any spurious excitation on the recording.
With toms, overhead miking will tend to give more of the stick and a punchier sound, whereas with single skinned toms, miking from underneath can produce more of the shell resonances.
Cymbals will sound clankier towards the bell and thinner towards the edge. With crash cymbals it's good to have the mike at least 18" away overhead to prevent the movement of the cymbal affecting the sound too much. Pointing the mike at the edge of the cymbal brings forth strange wooshing effects which may be useful, though not as standard cymbal sounds.
Having said that I'm going to keep it simple by sticking to cardioid dynamics, it would seem remiss not to quickly mention PZMs (pressure zone mikes). They are commonly used at home and in the studio, and most people agree that the performance of the Tandy model costing a modest £24.95 is very close to the professional items costing a great deal more. At this price it's certainly worth investing in one, or preferably in a couple for stereo recordings. They can be used for practically anything. They come complete with a metal mounting plate, but because they're picking up sound reflected from the surface on which they're mounted, their response can be varied by mounting them on different surfaces. Basically, a larger surface area will give a more extended bottom end and a harder surface, like a plastered wall, will give a brighter sound. As well as borrowing U87s from his Good Earth Studio, Tony Visconti also uses Tandy PZMs in his home set-up:
"I have a PZM permanently mounted on the sliding glass door that divides the hall from the room where the studio is, and I often use it for vocals or acoustic guitar, or for ambience. It has a great natural sound, and mounting it on the glass makes it very bright. They're also very good for piano sounds and I have a couple on the inside of the lid of my grand."
Irrespective of mike technique, poor foldback will normally result in a poor performance, especially for lead work and vocals where the artist has to be moved in some way to perform well. Try to use a reasonable set of headphones and take some time to create a good foldback mix, preferably with reverb in it — although some people prefer it dry, a touch of reverb on a singer's voice will tend to make them sound fuller and thus give confidence to the performance. If someone reacts strongly to using headphones or if they're having trouble singing in tune (even with one ear on, one ear off), you can try putting a small speaker in front them, behind the microphone, although this obviously means that you have to suffer the leakage into the mike. If it allows a better performance it can be worth it.
One of the main advantages of working at home is the absence of the studio clock and the resultant studio bill. Take the trouble to experiment because that's really the only way to actually understand how something sounds, and that's the whole point of the exercise. Before you get to positioning your mike and listening over the monitors etc, it's important to ensure that you're getting the best sound possible from source. If it's an acoustic guitar, make sure the strings have some life in them, try using your fingers or different picks, try different rooms and different positions in the room. Walk around the room listening to the sound of the instrument being played, find where you like it best and try placing the mike there — either on its own, or possibly as an additional ambient mike to mix in with a closer main mike. Any experienced engineer will tell you, it's all down to using your ears.
With a balanced low impedance mike you can afford to use a long lead (plus an extension for the headphones) and wonder about the house or flat trying out different naturally occurring sounds. Also try putting a miked-up loudspeaker in another room and using it as an effects unit during mixdown to add ambience. The above suggestions are no more than that — suggestions. The most important thing is to experiment and use your ears to derive your own variations. Either that or stick to synthesised instrumentals and save yourself the trouble.
Feature by Jim Betteridge
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