Beyond the Perfect Microphone: Find Your Audio Magic

Choosing a microphone is a fascinating process. Every process has a first step, and in our case, the first step is simple: context.

What is the context in which you are going to microphone a source (small club, huge open air stage, big band, close or far from the source, etc.)?

Why is this the first step? Because vocals (whether using an IEM monitor, normal monitors, recording for a voice-over track, for a live take in a movie, for a pianist, for guitar player that sings, for a live recording in a small smoky New York club), all have very different production needs.

Is tone not the most important thing when looking for a microphone? Yes and no.

Yes. Ultimately you want the microphone to complement the source and deliver an amazing sound.

No. A microphone that you can hardly use within the context of your application is no good to you or the artist you trying to mix/record for even if it delivers the ultimate tone you are after.

If tone is the only or first thing we look at, we might end up considering an option that is not viable within our usage parameters. Essentially, we are narrowing down the options, and to do so we should keep the following factors in mind:

1. Isolation of the source from other sources around it. This can vary from not being a consideration at all (like in a lead vocal studio session) to being a serious need (like on a crowded stage with loud instruments) while microphoning a very soft source or interviewing people in a loud street or commenting at a live event in a loud stadium filled with screaming fans.
2. Level of the source. How loud/soft is the source. A microphone that can handle high levels might not do so well when faced with soft sources as their intrinsic noise/level capacity combined with the pre-amp intrinsic noise could taint the source (i.e. like a hiss that you cannot hear on the snare, but you will hear when using the same set up for a voice over). The opposite is also true that microphones that can handle soft sources well might struggle with their counterparts.
3. Level before feedback. This is a combination of microphone, monitor choice, characteristics, and their relative positions (with normal monitors). We have all worked with “screamers” and “whisperers” (if you haven’t encountered a whisperer, I am truly glad for you), and the levels needed before feedback are very different. As said, the microphone is not the only variable in the equation, but it is one of them.
4. Proximity to source. Does the production (or the sound you are after) require you to microphone the source closely or from a distance? If from a distance, do you need to preserve the bottom end of that sound or can you go without it?
5. Sonic details needed. Does the production context require this source to be reproduced/recorded preserving its details and nuances, or is all you need a download of level so that you can push it above everything else?

The answers to these 5 questions (and a few more, I just don’t want to overdo it) will narrow down your options before you even need to engage your hearing. At this point of the choosing process, all you need to know is:

• A. The context of the source, which will determine
• B. What type of specifications the microphone you are looking for needs.

Do you need an omnidirectional microphone with a very low noise to signal ratio? Or do you need a hyper-cardioid microphone that can handle in excess of 120 dbSPL? Would the detail and transition period accuracy of a condenser microphone be essential?

To take the first step in the microphone choosing process, all you really need is to develop an understanding of the specifications of a microphone (those funny numbers and names that are written in the paper that comes with the microphone – readily available online). You don’t need to understand it all, but you need to understand enough to choose a microphone that on paper will thick all the boxes of your production needs.

Learning how to understand the specifications of a microphone (and their implication), is crucial in choosing and using a microphone correctly. For more, you can have a look here. That will narrow down the options substantially. Then the listening can commence.

Once we have narrowed down the options to a few, then your listening needs to guide you further.

I learned a very fascinating way of matching sources to microphones from a great engineer called Michael Stavrou.

It is a rather simple concept, based on establishing the hardness level a sound possesses. There is no hardness meter out there, hence your ears will have to suffice.

If a hardness scale existed, we would have on the one side of the scale “hard sounds” and on the opposite side “sweet sounds” (it is obvious that I am not referring to loudness, but to tone and perception of a sound).

If we were to use a 10 step scale, we would have the following: 1= Sweet 10= Hard, and 2 to 9 will be the in-between. Thus we can categorise sounds accordingly.

Let us use brass as an example: a trumpet would generally be a hard sound (H7), while a trombone generally has a sweet sound (H4).

Using the same “scale”, we can start to “measure” microphones for their hardness level. You can simply use your voice as a source and check out how the different microphones change your vocal’s intrinsic sweetness/hardness level (just use the same sentence i.e. count from 1 to 10).

Using the “hardness” scale, we will end up with microphones that range from H1 to H10.

Now that we have measured both sources and microphones, we can simply match them by using the universal “opposites attract” principle, compensating for the hardness of a source with the sweetness of a microphone and the other way around (a H3 sound will go with an H6-7 microphone and so on). This essentially prevents us from ending up with an extremely hard sound, with a very aggressive tone or an extremely sweet sound where the tone cannot stand up in a mix.

You will end up with a hardish microphone like the Senniheser MD421 (H7) on a sweet sound like a trombone (H4), or a Shure SM 57 (H8) on a “sweet” Vox valve amp (H3).

Let us recap:

1. You are probably in an environment (studio or rental company) where you often use the same range of microphones. Take some time (using your voice while listening with headphones to the different microphones) to record your discovery on paper. (Try to do this before your next tour / recording session)
2. Learn to listen acoustically to the sources you need to microphone, and discern what type of hardness / sweetness they possess.
3. Now the simple part: matching up a source to a microphone, remembering that opposites attract (an H7 source goes with an H3 microphone).

Listening is the most important aspect of sound engineering. It is the beginning and the end of all sound-related things, for all things we do should favour listening.

Something that always keeps on surprising me is the reality that engineers often do not know what to listen for (maybe I will write something about that in future).

Q: Why is this relevant to microphones?
A: Because the proof is in the pudding!

Once you finally sit down and started to listen (after you have selected a mic correctly and have placed it well), what you hear (the pudding) should prove that your efforts are well rewarded.

This is not as straight forward as it sounds as in most cases, what you will hear is unprocessed and not within the context of the mix in which it needs to fit. The challenge is to assess whether a sound will work simply by judging it at “face” value: before you do your magic and place it in the song.

At this point of the process mistakes can be made. For example, one of several common listening mistakes made, is the thinking that something sounds great just because it is “bright” or “warm” or “warm & bright”.

Even tough warmth and brightness is great, the question is how does the microphone/placement combo achieves that:

• Is it warm and bright simply because the frequency response of the microphone cuts a big chunk of mids?
• How does what you hear compare to what the source sounds like acoustically?
• Is it bright only on a small portion of the high end?
• Does it have presence?
• Will you need to fight its tone in the mix? Or will it fit in the mix?
• If the microphone gets you 75% there, will you hit 100% (or close to it) with eq? Or once you start to eq it, will you discover that the departing tone actually did not work so well? (For instance, a vocal that is really smooth and warm that lacks clarity, but is also sibilant – adding brightness will only compound the sibilance problem).

A tonic tone (or music to my ears) is a relatively neutral tone or a tone that will allow the engineer to do much once it is processed, both for his (or better his client’s) liking and for the mix.

Next time you listen to a microphone, remember that the sound you are hearing (most probably) is only one of several sounds that need to fit together. The more difficult it is to handle sonically, the more difficult (i.e. time consuming) it will be to make it fit into the context of your production.

Look for (or listen for) a microphone that offers a great “balanced” sound, one that preserves the natural tone of a source and delivers clarity. These 2 qualities together are always a precious prize. Clarity does not only rest on the presence of high-end frequencies in the tone, it is achieved by several factors. The more you achieve it without eq, the better, because then that sound will naturally stand out and fit in.

The famous song titled “A piece of Sky” sums up perfectly what it is to place a microphone properly: it is finding the angle, the position, that will reveal the glorious piece of sky you wanted and needed to see.

“The piece of sky” being a unique “take” or view that truly translates and enhances that “vibration” (that sound) so that it hits the listener precisely in that right spot. It is like looking at a view or a subject through a lens. Think of microphones as lenses, what the microphone sees is almost undoubtedly what it hears and picks up.

The question is, how do you place it so that the microphone not “only” sees the right “piece of sky”? How do you place it so that it translates beautifully that piece of “air” into a piece of “voltage’, a variation of electric current that most accurately captures the unique tones of the specific “vibration”.

To move from the philosophical to the practical, there are 3 microphone movements (in relation to the source you want to microphone).

1. THE BODY MOVEMENT, moving the microphone closer or further from the source.
2. THE FOCUS MOVEMENT, moving the microphone slightly left or right from the central axis of the source.
3. THE TONE MOVEMENT, turning the microphone at different angles from the source.

THE BODY MOVEMENT

Every sound has a “body” length (I am not referring to wave length). Every sound has a distance or proximity at which its tone is most complete. Take a snare-drum for example, most people think that the best microphone position for its sound, is a placement very close to its top skin. Yet the sound and tone of a snare-drum comes from its shell and the snare mounted on its bottom skin. The top head is simply the “trigger”.

When placing a microphone you need to start by figuring out how long its “body” is, or better how much of its “body” you want into this piece of sky you want to shoot.

The closer you get to the source the smaller (or partial) the body is.  Up to a point, the further you go from the source the more complete its body, beyond which the body will start to become smaller and further (softer).

Think of it as zooming with a lens: you can see the whole person, head to toes, just its head, or place a person on the horizon. The question is what do you want to see (hear)? If you are too close you will only see / hear a detail of the sound, if you too far you will see the whole picture but also many other things.

It boils down to knowing what you are looking for. However there are 2 sonic thresholds that are unhelpful to cross: too close to something and its natural beauty is “distorted”, too far and its prominence within the sonic stage (made up of all the sounds produced at the same time in proximity of the microphone) is gone.

Next time you place a microphone consciously think of the body of the sound and what you want of it. Too many engineers place microphone with no understanding nor insight, like a photographer shooting a tree while truly desiring a piece of sky!

THE FOCUS MOVEMENT

This is not true for all instruments but it is true for most (especially voices, wind instruments, most string instrument). Acoustic instruments are not nicely package symmetrical sound sources. They are “living” things, as such their sound production is often not symmetrical, therefore what is true on the left side (of the source) is not so true on the right side.

A voice is a very good example of this. Put your headphones on, listen to somebody speaking or singing closely (via a microphone), then imagine a central line (i.e. the nose) and listen to the same person moving the microphone to the right and the left. You will probably notice a difference between the 2 sides. In some people this is very slight in others it is very significant. In some instruments this is very remarkable.

I call this the focus movement, think of it like rotating the focus ring of a lens until the subject is in focus. So it is for you when you discover the right side of the “moon”. You will notice that something about the sound “got into gear” or better, it become suddenly more focus more “together”.

THE TONE MOVEMENT

Lastly turning the microphone at different angles from the source will award you a palette of different colours / tones. Because the frequency response of a microphone changes at different angles, changing the angle, gives you the opportunity to smooth-out the tone. For instance, you placed a microphone on an electric guitar amp, you did it well. You are happy with most of what you hear, but for the fact that is a bit too bright. Because the polar pattern of a microphone is narrower at high frequencies, rotating the microphone away from the central line will make the tone less bright and therefore more LF will be present.

Rotating a microphone really aids to your tone control!

NB: For vocals there is a further movement possible (if you are recording), up and down in relation to the mouth. Down towards the chest, up towards the forehead. The sound will change very remarkably in tone.

I made a truly amazing personal discovery once I realised that our ear-brain combo is the most sophisticated piece of audio equipment on the market (make sure you look after it and value it).

Vibrations traveling through the air end up stimulating one or more of the 25000 “trigger” cells we have in our ears, more precisely in an inch long chamber known as the organ of Corti. Each of these triggers are connected to the brain where the received stimuli are further analysed. If you could see a real-time brain scan, you would see it lighting up in different parts of the brain at different times as stimuli are processed and interpreted.

That Christmas tree lighting event hopping around your grey matter ends up processing things like tone, time, phase, levels and few other variables which in turn end up giving you the sensation of sound, making you experience the pleasure of music, or rather the pleasure of its anticipation.

Furthermore, the combination of all these variables analysed at the same time ends up giving you some truly important information, like location of the source in terms of distance and relative angle, which translates into depth and staging of a sound or sounds within a sound field. The entire wonder (our perception of sound staging) is based on our brain’s capacity for comparing data between the left and the right ear. If you close one ear, you would essentially lose a big chunk of that ability.

What does this have to do with microphones?

Every time we place a single microphone in front of a source, in essence, we close an ear. We loose (to a great extent) the intrinsic depth of the sound within its sound field; we also lose part of its tone as different parts of the instrument contribute differently to its acoustic tone. Unfortunately, by just using one microphone quite close, we end up focusing only on a portion of its natural tone.

Using two microphones with specific angles and distances between them, creates a similar pick-up to what our two ears do naturally (because the two microphones end up capturing phasing and time differences of the same sound that can be conveyed to our ears).

It goes without saying that this is not always or often practical or logistically viable (or even justifiable, because in most cases, live events run mono anyway). Talking about microphone positioning without mentioning stereo techniques would be like eating pasta without knowing or experiencing the undeniable taste of freshly grated parmesan on it. Can one eat pasta without parmesan? Absolutely (for the record some pasta types do not need or require parmesan on it), however never having tasted parmesan would imply that you never truly experienced pasta or food.

It is worth mentioning that stereo techniques that mono well are also helpful in live and in broadcast scenarios. In my book I mention that if you do not know how to take advantage of stereo techniques, your are definitely poorer for it.

To find out more, visit the DPA microphone university where you will find loads of great tips, among which a bunch of stereo microphone techniques explained.