The importance of being Plaice
Updated: Mar 11, 2021
A plaice is, apparently a large edible marine flatfish of Western European waters.
Can't say I knew that, and this being The Audio Blog, my guess is that you didn't either, and we are all fine with it.
And no, I haven't developed a sudden interest in Mediterranean flat fishes.
What we are talking of is the most important issue of microphone placement, which can at the same time tremendously improve your recordings, save you a lot of money in misguided upgrades of microphones but, of course, rob you of all the fun of buying shiny new toys.
(Got the title pun, now? Yes, I agree. It's pretty lame).
Do I need to upgrade my microphone?
Well, maybe, but most often no, you don't.
You may remember that in the order of Stuff That Matters for a great recording (and thus makes it possible to produce a great mix, which makes it possible to have commercial success and eventually you getting that villa in Malibu with your royalties) music, arrangement, performance and recording space come first, followed by the ability of setting the gains right (rather obvious but all too often botched by hobbyists).
Then there's the choice of microphone and the rest of the gear, in descending order of importance.
But microphone is not just about the microphone hardware.
How a microphone sounds is due, of course, to its design, principle of operation and physical construction. It's very hard to make a pencil SDC sound like a U47, or a 57 like a passive ribbon mic.
But every microphone has, hidden inside, at least half a dozen timbres, and most often double that.
How many you can extract, however, depends on the recording space.
Placement and the recording space
That's because where you place the source in your recording space, and where you place the microphone with respect to the source can change the sound dramatically, arguably more than using a completely different microphone but leaving the position unchanged.
At least when we're talking of the same class of devices (say condensers, moving coil dynamic mics, ribbon dynamic mics, and so forth)
The effect of the position of the source should be fairly clear: every recording space, even treated ones, produces some room reflections at least at certain frequencies.
These reflections will filter the original sound in slightly different ways depending on where the source is.
If you have tried to play some music on your mobile phone while keeping it in your hand and then placing it on a laminate table, you know what I mean. The table top reflects immediately bass frequencies and the bass becomes much more prominent. It's the same reason for which if you put your mixing speakers near a well, you'll do well in using the onboard EQ to reduce the low frequencies.
In a completely anechoic chamber, the source location wouldn't matter. But nobody records ever in an anechoic chamber (I guess) and it's in general a rather unpleasant place to be, so in any real world situation, the source location matters quite a bit.
The same applies to microphones.
Everybody knows (or intuitively understands) that sound loses energy with distance (and some may remember that high frequency components have less energy, so they dissipate faster); so it's pretty intuitive that close-miking a source will increase the level of the direct signal with respect to the reverberation/reflection, leading to a more "dry" sound, with less reverberation
But position is not only distance; it's also a lot about angle with respect to the source (in two dimensions, higher/lower and left/right)
Placing the microphone at different angles will yield dramatically different sounds.
That's both because, once again, the pattern of interference with reflection changes quite a lot.
But it's also because, while most instruments have defined "fronts", different frequencies often irradiate in different directions from this front. And most instruments (yes, even people) irradiate in all directions for sufficiently low frequencies.
Close-miking the left side of a cello will sound wildly different than the right, and the same goes on top or above, with exactly the same microphone. The same for an acoustic guitar There are at least half a dozen position with which you can use a single mic to close-record an acoustic gutiar and the same mic will not sound anything alike!
And if you move at a distance, you will capture not only more reflections/reverberations: you will capture more of the whole spectrum of the source (as it is in that specific position) so yelding a quite different result.
The recording space
So source and microphone position matter. How much?
Well, it depends on the recording space.
If the recording space is very reflective, the filtering will still change but only very prominent effects will be apparent (such as the bass boost above).
For low frequencies you will have very prominent nulls and crests (places where certain low frequencies - aka bass notes - are completely canceled or doubled in volume.
Comb filtering will happen at some higher frequency band (which exactly will depend on where you are) so you will find very few positions of the same microphone that will yield usable results, outside very close-miked ones.
And even then, you probably won't be able to EQ and boost much without getting some nasty sounds - the problem is not the microphone, but the room reflections.
You can still experiment with certain positions and get some more timbres out of a microphone than just the "directly in front at close range" on - for example, a trick that often works well with certain types of distorted electric guitars is to place the amp near a wall and point a microphone to the wall rather than the cabinet!
In general tough a bad room will yield mostly, if not exclusively bad results, so no need to upgrade the microphone. Fix the room first!
However, if your recording space is more controlled, you have even more choice.
That's because "controlled" does not mean devoid of reflection, but that you know how certain areas behave, large low frequency position-dependent swings are largely smoothed out, there's no nasty high frequency flutter echoes, reverberation is diffused and less correlated with a specific source and so on and so on.
That means that you will be able to vary distances more without excessive reverberation and when varying the angle, the dry sound will be even more "dry" and different with the same mic than in a bad room. You will "lose" however, the broader impacts on placement of a very reflective space.
More of the unadulterated sound of your microphone will allow you to truly judge its timbre and capabilities, and less reflections mean that you will be able to use more distant positions (for then turning the gain up to reach the same level as a closed mic recording) without drowning in reverb and keeping the ability to EQ boost in post.
The importance of not being a fish
In conclusion, if you're serious about getting good recordings you've got to realize that positioning is literally a multiplier of the capability of your microphone and often you can find a different, more suitable sound simply moving the source and the microphone about and monitoring the results.
And that (as of the usual mantra) in a bad room you have no idea how your microphone is really sounding.
In a typical acoustic guitar session, for example, finding the "right" spot in a reasonable space may take from 10-15 minute to an hour.
Take notes, use gaffer tape on the floor to remind yourself where things were and in general take your time, and monitor how things sound in your headphones before getting back to the recording laptop and pushing "R".
Forgetting or not using placement as a tool is a bit like being a fish - enough brains to swim but somewhat limited. Don't be one!
So, do I need to upgrade my microphone or not?
It's true that every microphone has a timbre, but before looking at the cash in your wallet, it's worth asking yourself:
"does my room sound good?" (so that I can use more distant miking positions)
if yes, "have I tried a different placement (or a dozen) for this mic I have?"
You'll be surprised how many times looking at these two answer will save you the cash of another mic giving you exactly the same unsatisfactory results.
But if you've done all that... go ahead and get yourself a new mic.
After a while you'll be like me and have over 20 or 30 in your locker.
But it will be for a good reason. Microphones sound different (even mics in the same broad class) and they're worth having or using. Just make sure you can hear the difference and you can't achieve the same result with what you have!