The two golden rules of microphone placement
There is nothing in audio as important as microphone placement.
So what are the ground rules for getting this right?
Two microphones…
The Shure SM57 - $99
The Neumann U87 Ai - $3,599.95
At such wildly different prices (offered by an online
retailer in the USA)…
You should expect these microphones to sound different.
And they do.
Whether there is $3,500.95 worth of difference…
Is open to debate…
But microphone selection is an important component of recording technique.
However there is one way to make much more of a difference to the sound…
Using the same mic…
Just move it by 30 cm (around a foot).
Microphone positioning makes a hugely greater difference…
Than microphone selection.
And improving your microphone’s position costs nothing but…
A little time.
The importance of microphone placement or positioning cannot be overstated.
The professional way to do it…
For any instrument or voice…
Is to start from a point that is known to be good from experience.
Then move the mic to different locations…
To find the ultimate sweet spot.
This is best done with two people…
The engineer and his or her assistant while monitoring in a separate control room on loudspeakers.
It is more difficult for one person to do this while monitoring on headphones…
But the objective is the same.
But suppose you don’t have so much experience yet…
Or none.
Suppose this is your first time setting a microphone…
Where do you start?
Let’s imagine you have an acoustic instrument to record…
To keep things simple, in mono, with a single mic.
Let’s say that you only have one mic so microphone selection isn’t an issue.
Let’s suppose the instrument is a guitar…
And suppose you want to achieve a natural sound.
Step one is to find out where in your recording space the guitar sounds best.
Normally it is better to be well away from walls and hard surfaces other than the floor…
But try out a few locations and see what difference there is to the ear.
There might not be much difference in a small room with similar surfaces all round.
But if you have the luxury of recording in, say…
A local hall or community centre…
There may be more options.
Similarly if part of the floor is carpeted and part not…
Soft and hard surfaces will affect the sound differently.
So, once you have a good position for the instrument…
Walk around while the musician plays…
Find a spot that is good to listen from…
And so…
Golden Rule No. 1…
“Point the microphone at the instrument from the best listening position.”
It would be an odd thing to do…
To place the microphone somewhere other than the best listening position.
This might seem like stating the obvious, but…
Often the obvious solution to an issue is…
The best solution.
Or at least try out the obvious solution first before…
Going along seemingly less promising routes.
There are exceptions to this rule…
Ambience mics, the side mic in an MS pair…
The fine art of angling the mic slightly to fine-tune its response to the sound source,
etc.
But these are the very few exceptions that test the rule…
But don’t by any means break it.
So once you have placed your microphone on a stand…
In the best listening position…
Pointing at the instrument…
You’re good to go on to…
Golden Rule No. 2…
“Move the microphone closer to the sound source.”
Remember that we’re aiming for a natural sound here.
But while the best listening position to the human ear…
Would seem to offer the most natural sound…
We have to consider the differences…
Between the ear and the microphone.
The human ear is connected to the human brain.
The human brain, which some consider to be the most complex thing in the entire universe…
Can process the sound picked up by the ears…
And make sense of it.
It can separate out the ambience and reverberation of the room and…
And focus in on the direct sound from the instrument.
The microphone…
Even if it is a directional microphone…
Cannot do this anywhere near as well.
So what sounds good to you…
In the best listening position…
Won’t sound as good to the microphone.
There will almost certainly be too much reverb.
To focus in on the direct sound of the instrument…
All that is necessary…
Is to move the microphone closer.
How much closer should be determined…
By experiment.
For a natural sound, aim to…
Achieve the best balance between…
The direct and reflected components…
As judged from the sound coming from your monitor loudspeakers.
Having followed Golden Rules 1 and 2…
You’re good to go.
If your room has good acoustics and…
A low noise background, and…
You are working with a good musician who…
Plays a good instrument…
Your recording will be…
First class.
Of course there is more to microphone placement than these two rules, especially if…
You’re aiming for a larger-than-life sound…
Which is often the case other than in classical music.
Stereo techniques, and methods of recording groups of instruments and voices…
Require additional considerations.
But the two Golden Rules will get you…
An awful long way…
Along the route to success.
I highly recommend them.
I’m David Mellor, Course Director of Audio Masterclass
Thank you for listening.