Using A Stereo Microphone – A Primer

Stereo Recording stereo microphone can prove useful in the multitrack mixing environment. Practically all of our recordings today involve stereo. While surround Hearing In Stereo releases are becoming more common, even these are largely The two primary cues that our brain based on a primary stereo image uses to help us locate a sound enhanced by effects and ambient source in space are differences in sound to the rear and sides of the arrival time (phase) and amplitude listener. between our two ears. The process works pretty well in real acoustic The standard studio technique for spaces, but it’s confounded popular music production is to create somewhat by loudspeaker a stereo sound field from reproduction, where we hear sound multitracked recordings of coming from two discrete sources monophonic sources panned left- (the loudspeakers) as well as right, with delays and reverberation reflections from the surfaces of the added to create the sense of space. room. True stereo recording - capturing the full acoustic environment from a We can move the perceived location single vantage point using a process of a sound between the speakers similar to that of the human ear simply by changing the amplitude of provides a distinctly different kind of the signal fed to each speaker - this sound. is what a pan pot or stereo balance control does. Another way of Single-point stereo miking has long changing the apparent location of the been used for classical music sound between speakers is by recording. Here, the goal of the sending the identical signal to both recordist is to capture and convey to speakers at the same amplitude but the listener the experience of delaying the sound to one speaker actually being in a concert hall with relative to the other. The sound the orchestra. This is probably still arrives first in one ear, then the the most common application of the other. Our brain tells us that the single-point stereo microphone due source of the sound is coming from to its convenience and its ability to the direction of the ear which hears it accurately capture the sound of the first. acoustic space. Stereo microphone techniques need not be limited to In general we need an amplitude classical recording, however, and difference of about 15 dB in order to are often appropriate for recording in make a sound to appear to be an intimate jazz club or a church. In coming from one speaker or the addition, recording such physically other, but this is dependent on the large instruments as pianos, drum program material. At low kits, or large vocal groups with a frequencies, a 15 dB amplitude difference between speakers makes demonstrated mathematically that for practically no difference in apparent lower frequencies, level differences location. The bass would have to be between speakers are translated into 25 to 30 dB louder on one channel phase differences, with the ear on than the other in order for it to be the side of the louder speaker perceived as being off-center, and leading the other ear in phase. many playback systems do not have sufficient dynamic range to allow This phase shift varies approximately this. linearly with frequency, so it represents a difference in time-of- Mixing engineers almost always pan arrival fairly accurately. At high bass to the center for this reason. In frequencies, the phase differences addition, engineers who were raised get swamped out by amplitude on vinyl learned that moving a large differences, which is what our brain amount of low frequency energy off uses as a cue to their position. center causes the needle to jump out of the groove or damage the disk The real world throws in some cutter. Back when “mastering” was wrinkles like the shape of the the first step in the record listener’s head, but the bottom line is manufacturing process, it was fairly that in spite of a lot of theoretical and common for the mastering engineer practical obstacles, we can actually to separate the lows from the highs, hear stereo when listening to mix the two low frequency channels loudspeaker playback. As recording to mono, and put the tracks back engineers, it’s our job to capture the together, assuring that the bass was sound field so that it can be centered. realistically reproduced through loudspeakers, and there are several With CDs, those mechanical ways to do so. problems went away, but the problem of dealing with a large low Stereo Microphone Applications frequency amplitude difference between channels in order to create During the 1930’s, both Blumlein in the illusion off-center bass still the UK and Harvey Fletcher (of the remains. Phase difference due to the Fletcher-Munson loudness curves) at different path lengths from a source Bell Laboratories in the US to each ear still works at low developed techniques for using frequencies however. This is the microphones in pairs for recording in mechanism by which we are able to stereo. The results of their locate low frequency sounds in the experiments and demonstrations are stereo field. all still relevant and applicable today.

Alan Blumlein, an engineer and Typically a stereo mic setup is acoustician at EMI in England is appropriate in situations where generally considered to be the father acoustics are good (or at least not of stereo recording and reproduction detrimental to the sound) and when as we know it today. He the group being recorded is playing all together and is well balanced. As foot, and sometimes with a baffle you might surmise, this best placed between them. describes orchestras, jazz bands, and acoustic folk artists. Since An ideal coincident pair has the classical music is traditionally diaphragms of the two microphones performed in good sounding halls, a occupying the same physical space. well-placed stereo microphone setup Since that’s physically impossible, is frequently all that’s required to we make do with “pretty close.” This capture the performance accurately. can be accomplished by positioning And there’s nothing like a stereo two individual microphones with their recording from a good seat in the heads just about touching, and with house to hear what your band an imaginary line passing through actually sounds like. both diaphragms.

Typically classical stereo recordings The important concept here is that are plug-and-play with no overdubs the two microphones work as a pair or punch-ins, no mixing or ducking, to give us both the amplitude and and perhaps only some editing phase differences we need in order between alternate takes. Stereo to locate a sound in space. miking isn’t limited to recording of a fully integrated performance, Coincident Arrays however. In the modern music studio, recording single instruments Coincident arrays require that the with a wide frequency range and microphone diaphragms be placed large radiating area such as acoustic as close together as possible. The guitars, pianos, and percussion LSD-2 incorporates two multi- instruments can add a useful pattern microphone elements in a dimension to a multitrack mix. In single case with the diaphragm of addition, a stereo recording of a well one positioned directly above the balanced instrumental or vocal other, making it very near to an ideal section as part of a multitrack project coincident stereo mic. can add realism as well as save studio and mixdown time. The mics in a stereo array can have a cardioid, bi-directional, or in certain Stereo Microphone Arrays cases omnidirectional directivity pattern. Since the mice are either Stereo microphone arrays fall into pointed in different directions or are two general categories: coincident some distance apart, each mic gets and spaced (sometimes called “near a different perspective on the sound coincident”), which describe how the field. Since a directional mic’s two microphones are positioned sensitivity varies with angular relative to each other. position, any sound originating off center will appear at a different level A spaced stereo pair has the two in each mic of the pair, giving us the microphones separated by a fairly amplitude cue to locate the sound in small distance, usually less than a space. Because the microphones are weaknesses and it’s up to the located in essentially the same engineer which arrangement to use. space, a coincident pair has the advantage of mono compatibility – As a broad generalization, the that there’s little or no loss of content coincident approach produces a when a coincident stereo recording stereo image that’s more focused, are summed to mono. This is more allowing the listener to more important than you might realize. precisely pinpoint a sound source. Although you may not consciously By contrast, the spaced array yields listen in mono very often, consider all a less precise stereo image, tends to the people who wake up to clock produce recordings that are more radios or still hear television audio open-sounding with a wider stereo through a single loudspeaker. If your spread. stereo recording contains too much out-of-phase information between Either technique can work well in a the channels, certain frequency good recording environment, but in a ranges or overall ambience can drop room with a lot of nasty reflections out when mixed to mono, leaving a that you can’t do anything about, thin sound. spaced omnidirectional mics or coincident bi-directional mics are Spaced Arrays more likely to save the day than the more common coincident cardioid Although the LSD-2 by nature of its arrangement. construction doesn’t lend itself to use in a spaced array (unless you buy Some engineers have used a two of them), we would be amiss in a combination of spaced and general discussion not to mention coincident setups, combining them to such an arrangement. In a spaced take advantage of the best stereo array, the diaphragms of the characteristics of each technique. two microphones are positioned several inches apart and are typically The LSD-2’s design allows you to splayed outward from their center experiment with different coincident line. The spacing causes the arrival arrangements easily, and the only time from a source to be slightly way to tell which works best is by different between the two mics, listening. giving a phase cue for directional location. Spaced mics often give X-Y Coincident pleasing spaciousness to the recording, but their mono The X-Y configuration is what most compatibility is poor. people think of as a “stereo pair”. The common starting position when Choices, Choices using cardioid mics is to splay them 90 degrees apart with the line Both spaced and coincident arrays bisecting that angle pointing “straight have their strengths and ahead”. Hypercardioid mics usually want to be splayed a bit further, Experience with the LSD-2 shows around 110 to 120 degrees. that 110 degrees is a The mics are positioned at a good starting distance from the source that gives a point. good balance between direct and There’s no reverberant sound, and the angle dot to mark between the mics is adjusted to this position, adequately cover the width of the but it’s source. This is counter-intuitive, but conveniently Align for to get a wider coverage, the angle located in 110° between the mics is decreased. The line with the important thing to keep in mind is breakpoint of that 90 or 110 degrees is just a the low cut starting point, with the final decision filter resting with your ears and good indication on judgment. the switch for the upper X-Y is simple to use since you get microphone. left and right channels directly from the mics. The mic that points toward With the upper capsule rotated to the left side of the source becomes this position, the center line for the the left channel, ditto for the right. pair is located at 55 degrees. Again, there’s no dot to mark this, but it’s in When using a stereo pair in a mix line with the cardioid marker for the with other mics, you don’t always lower microphone switch. Aim that have to pan or assign the pair full left cardioid and right, you can put them marker to the anywhere you want. You can even center of reverse them. Whatever sounds your sound right is right. source (the Studio On the LSD-2, you’ll notice a series Projects of engraved dots around the ring at name will be the top of the grill of the lower to the left as microphone capsule. The dot above you face the microphone) and you’ll the Studio Projects name is “front- have a good starting place. and-center” with the other dots marking 45 degree increments. The Remember that changing the angle front of the upper, rotatable capsule between the capsules is done by is marked with a single dot. rotating the top capsule relative to the bottom one. Rotating the top Don’t forget to note the pattern capsule will change the center line switches. For X-Y operation, be sure for the pair, so if you change the to switch both microphone elements angle between mics, you’ll need to to the cardioid position. re-center by turning the housing Because a condenser microphone slightly in its shock mount. creates its bi-directional pattern by mixing of the outputs of two separate The distance from the source where diaphragms, its pattern isn’t perfectly the direct and reverberant sounds symmetrical, but the LSD-2 in the are equal in amplitude is known as figure-8 setting does an excellent job the “critical distance.” Normally the in a Blumlein setup. mic position is always forward of the critical distance, but how far depends While the bi-directional mic has on how much reverberation you want equal sensitivity in both directions, in your recording. the polarity of the signal produced by sounds arriving from opposite Since the lower capsule is pointed directions is opposite. Therefore it’s toward the right side of the source important to be aware of which side when the mic is in its normal is “front” so you can position both orientation on a stand, the XLR capsules so that the polarity between connector at the split end of the the stereo channels isn’t inverted. LSD-2’s cable will be the right channel. If the mic is hanging with The front of the fixed capsule is the the cable going upward toward the side of the body with the Studio ceiling, left and right will be reversed. Projects name. The front of the rotatable capsule is marked with the The Classic Blumlein Array single dot. Viewed from above, if you rotate the top capsule While Blumlein studied and counterclockwise so its dot lines up documented many different with the second dot around the lower microphone arrangements for stereo capsule ring, you’ll have the two recording, the one that most often capsules set correctly for the classic bears his name is a variation of the Blumlein configuration. X-Y arrangement, employing two bi- directional (figure-8) mics rather than The 45 degree dot (above the figure- cardioids. In the classic Blumlein 8 of the pattern selector for the lower configuration, the microphones are capsule) is your center mark. Aim always crossed at right angles (90 that toward the center of the sound degrees) and positioned so that a source. line bisecting the angle between the capsules is aimed toward the center Again, like the X-Y pair, the lower of the source. capsule points toward the right in the normal orientation, so connect the Many people consider the classic red-jacketed XLR to the right Blumlein to be the perfect stereo channel of the recorder. microphone. Blumlein worked with ribbon microphones which, by nature Since the bi-directional mics have of their design, have perfectly considerably more sensitivity toward symmetrical directivity patterns and a the rear than cardioids, the Blumlein perfect null at 90 degrees off axis. array will pick up more reverberation and ambience than an X-Y pair in Mid patterns in an M-S setup the same location. You’ll probably painless. want to position the Blumlein pair To use the LSD-2 as a traditional somewhat closer to the sound M-S array, select the cardioid pattern source than you would an X-Y pair in on the lower capsule and the bi- order to avoid an overly reverberant directional pattern on the upper recording. capsule. Rotate the upper capsule 90 degrees counterclockwise If the acoustics of the room are poor, (looking from the top) so that the dot the classic Blumlein is probably not on the rotating ring is lined up with the best choice, but in a room with the second dot on the fixed ring. great acoustics, it’s hard to beat. Position the microphone so that the lower capsule faces the sound M-S Coincident source. Note that you can use either capsule as the Mid or Side mic, but Another popular coincident since we put our name on the front, microphone setup is known as M-S, you might as well point it toward the for Mid and Side. An M-S stereo performer setup tends to be more fussy about the acoustical environment than X-Y M-S Arithmetic (more accurately, it’s easier to find a workable position an X-Y pair than M-S is more complex than the other an M-S when the acoustics aren’t so configurations we’ve described great) but M-S offers a greater because the output signals of the degree of control than X-Y. two microphones don’t translate directly to left and right channels. In M-S, a forward-facing mic (the Mid Some electrical manipulation is mic) is positioned for a well balanced required to derive meaningful left- mono pickup of the sound source, right stereo from the Mid and Side and a sideways-facing bi-directional outputs. mic (the Side mic) contributes width information. We usually use the terms “encoding” and “decoding” or “matrixing” to Since the figure-8 directivity pattern describe the process used to has a null in what’s the forward translate M and S signals to left and direction of an M-S pair, it (in theory, right. To understand how this works, and pretty much in practice) does not we need to use some simple change the overall balance algebra. established by the Mid mic. By convention, positive pressure on The Mid mic is conventionally a one side of the diaphragm of a bi- cardioid pattern, but it can also be directional mic produces a positive omnidirectional or bi-directional. The output voltage, while positive selectable patterns of the LSD-2 pressure on the opposite side makes experimentation with different produces a negative voltage. A cardioid mic produces a positive voltage for a positive sound pressure Matrixing toward its most sensitive side. The outputs of the two mics oriented An M-S matrix can be constructed as described combine in phase when from a pair of transformers with split a sound is arriving from the left side secondaries wired to produce the of center and out of phase for a sum and difference of the voltages at sound arriving from the right. the two primaries. Follow the Because of the bi-directional schematic below (courtesy of Jensen microphone’s sensitivity null on- Transformers) and you’ll see what center, an on-axis source is heard by happens. The dots on the the Mid microphone only. transformer windings indicate polarity. The basic M-S relationships are as follows:

Mid + Side = Left Mid - Side = Right

A sound arriving from the left produces signals from both the Mid and Side mics which are in phase, By simply adding them, we get the left channel signal. A sound arriving from the right will be out of phase between the mid and side mics. To Let’s work backwards from the get the right channel, we must outputs. Pin 2 of the Left output is subtract the Side signal from the Mid connected to the dotted end of one signal. We do this by inverting the winding of the Mid mic transformer. polarity of the Side mic before it to The other end of this winding is the Mid mic signal. connected to the dotted end of one winding of the Side mic transformer, Taking this one step further, we see and the other end of the Side mic that: winding is connected to Pin 3 of the Left output connector. This puts the L + R = (M+ S) + (M- S) two windings in series and in phase. = M + S + M - S = 2M Pin 2 of the Right output is connected to the dotted end of the Notice that when the left and right other secondary winding of the Mid channels derived from an M-S pair mic transformer. The opposite end of are summed to mono, the side mic this winding is connected to the un- cancels out of the equation leaving dotted end of the Side mic only the forward-pointing mid mic for transformer, and the dotted end of perfect mono. that winding is connected to Pin 3.

It’s this backwards wiring of the lower secondary winding on the Side mic transformer that does the the relationship between mid and subtraction to give us the Right side mics, so you have to be aware output. of what’s in the signal path.

There’s a hitch with using One more tip: Since the channel transformers at the mic end of the inserts on most modern consoles are recording chain. Since you can’t unbalanced, a simple single ended pass DC through a transformer, sum and difference circuit based on phantom power supplied by the op-amps can be constructed without console or outboard preamp won’t much difficulty. make it to the microphones. You could add a phantom power supply Keeping it M and S to a transformer matrix but a more satisfactory arrangement is to One approach favored by some field connect the mics directly to the recordists is to record the mid and preamp and decode the line level side signals directly, connecting an preamp output on its way to the M-S matrix only in the monitor (or recorder. headphone) path when recording. This allows you to hear a normal This can be done with transformers, stereo image while deciding where to however the Jensen JT-MB series place the microphone, and for shown in the above diagram are not monitor in stereo while tracking. designed to operate at the high Afterward, you can “remix” the Mid output level typical of a modern mic and Side tracks through an M-S preamp. Audio Engineering decoder in your studio and adjust the Associates is one source for an M-S width while listening in a familiar decoder designed for these levels. monitoring environment.

Decoding at the Console Inserts A few mic preamps have M-S decoding built in. One of these When using a console’s mic preamps, together with the LSD-2 preamps, a line level decoder can be and a stereo recorder makes a very conveniently patched into the convenient and compact location channel insert points. In a typical recording package. M-S decoding is console, the insert send directly also found in many DAW programs. follow the mic preamp while the This is a good solution for the home insert returns come before the recording engineer with a studio channel faders. With a decoder based around a computer, or for patched between the M-S mic post-production of a raw M-S channel insert sends and returns, the recording. faders act as if they’re directly controlling left and right stereo mics. The Console as a Matrix

The mic preamp gain trim and You can also decode the M-S anything else ahead of the insert signals using a mixing console and a point (EQ on some consoles) affects simple “Y” cable. pencil and a rubber band trick will do the trick.

Start with the Mid mic fader all the way off or mute the channel. Set the input trims on the Side channels in Connect the Mid mic to one channel the ballpark for what you’ll be and center its pan pot. Split the Side recording, solo both side mic mic’s output with the Y cable and channels together (or temporarily connect it to two other (usually pan both of them to the same side). adjacent) channels. Get some sound going into the mic, and adjust either of the trims to null the output. When you get pretty close to the null point, raise the monitor volume so you can really nail it. This makes the level of the two out-of-phase channels equal.

Un-solo (or reset the pans), start the music, and check your levels. As a starting point, when the music is as loud as it’s going to get, analog VU Pan one of those channels full left, meters should reach around -3 VU. pan the other full right, and invert the A good starting point with a digital polarity of the right-panned channel. meter is slightly below -20 dBFS. If you’re very far off, reset the trims on If your console has a polarity (phase) the Side mic channels, then re-null to reverse switch, use it as shown in get the gains exactly the same. the diagram above. If not, swap Pins 2 and 3 in one branch of the Y cable Now listen to the left and right to give the required polarity outputs. It should sound positively inversion. (Mark that reversed awful because you’re listening to the polarity connector!) two channels out of phase and everything is off-axis to the Side By the way, it’s OK to “Y” together microphone to boot. However, when two phantom powered inputs if your you bring up the Mid mic fader, you’ll console doesn’t have phantom start hearing real stereo. Leave the power switches for each channel. Side mic faders in their starting position and adjust the Mid fader for Once you have things connected as the desired stereo spread. show, bring the faders of the two side mic channels up to their working Be sure to check your recording level position. It’s handy to tie them and preamp gain (be sure you’re not together since they’ll always be clipping up front) before starting the moved as a pair. A broken piece of session. Small level adjustments can be made with the mixer’s master fader, but if you’re way off base the output from a stereo reverb unit when the crashing crescendo which can be added to taste. As a comes, you may need to re-trim to rule of thumb, mic pairs should be avoid clipping the mic preamps. It’s a less than about 75 feet apart to avoid bit awkward to juggle all those faders echoes. if you need to change overall gain once you’ve set things up, but once Fans of this technique believe it may you get the hang of it, it’s not too be the best of all possible worlds, difficult. providing the spaciousness of the near-coincident array, the location Double M-S accuracy of a coincident array, and the mono compatibility of an M-S One of the conundrums with M-S recording. And we get to sell you stereo, actually with any single-point another LSD-2. stereo recording setup, is that when the microphone is positioned to get Doin’ The Blumlein Shuffle good detail, it may not pick up sufficient room ambiance, yielding a Alan Blumlein conceived stereo not rather dry sounding recording. only as left and right signals, but also Moving the mics further back into the in terms of a sum (L+R=M) and reverberant field will capture more difference (L-R=S) that we know ambiance, but go too far back and from the basic M-S equations. He you’ll lose the up-front clarity. proved mathematically that these relationships could be used to modify Curt Wittig and Neil Muncy, two the “stereoness” of recordings. engineers who specialized in What’s particularly cool is that this minimalist recording, when searching actually works in practice. By for a solution to this problem, came creating a sum and difference from a up with a setup which they dubbed stereo signal, you can manipulate Double M-S. them like the outputs of an M-S microphone, putting them back In Double M-S, one M-S pair is together with a different perspective. positioned as close to the source as necessarily to achieve optimum Decreasing the level of the L-R detail, for the moment ignoring the (difference) signal with respect to the balance between direct and ambient L+R (sum) signal narrows the stereo sound. A second M-S pair is width. This is no big deal since you employed for the sole purpose of can accomplish the same thing picking up ambient sound. simply by panning the left and right channels toward the center. The “ambience” pair is placed However, by increasing the level of beyond the critical distance, the difference signal relative to the sometimes even facing the rear of sum, you can increase the apparent the hall. Its output is mixed with the stereo width, effectively turning the main M-S pair to provide the desired pan pots beyond their stops. amount of ambience. Think of it as You can take this too far, ultimately things out. A good place to start is punching a hole in the middle of the boosting the difference signal by stereo image, but sometimes three to six dB in the range of 400 to unconventional procedures yield 600 Hz. This sounds complicated, creative results. but it’s easy to understand what’s happening if you follow the block Blumlein also discovered that the diagram of the mixer setup below: image accuracy of a stereo pair could be improved by applying an equalizer to the difference signal. The process of equalizing the sum and difference independently before combining them into left and right is called “shuffling,” effectively creating a frequency dependent width control.

Since most microphones are less directional at low frequencies, shuffling can help to improve the ability to localize bass instruments in the stereo field. Inserting equalizers Here’s how to make a TRS “Y” cable in line with the sum and difference for splitting a balanced bus output derived from a stereo signal is a into normal and reversed polarity useful way to experiment with this signals: process.

If you have a 4-bus or even a semi- 4-bus console (such as the Mackie 1202-VLZ Pro) and some Y-cables (a couple wired for polarity reversal if your console lacks polarity/phase reverse switches), try shuffling a stereo recording. Create the sum and difference signals on one pair of But if you have only a simple stereo busses. Then return the sum (Mid) mixer, thanks to a clever method and difference (Side) signals to conceived by the late stereo guru another pair of line inputs just as if Michael Gerson, you can still shuffle. they were the two outputs of an M-S mic pair. Assign the outputs of your Gerson observed that inverting the M-S mix to the mixer’s main left and polarity of the left and right outputs right outputs. and cross-coupling them back to

another pair of inputs was electrically Now you’re back to stereo, but you equivalent to Blumlein’s classic sum can experiment with the balance and difference circuit. Here’s how to between sum and difference signals set up this shuffler. Note that left and add some equalization to spread output is connected to the inverted channel that’s panned to the right A Non-Stereo LSD-2 Application and the right output is connected to the inverted channel panned to the While the purpose of this paper is to left. This is the trick that makes it describe how to use the LSD-2 as a work. stereo microphone, there’s a handy studio application worth a mention.

When working with a singer who plays an acoustic instrument, as engineers, we frequently prefer to record the instrument and vocal in separate passes and on their own tracks to allow us to apply different EQ to the voice and instrument, and

The thing that you need to watch for when the inevitable “Can I just fix with this setup is that there’s really a that one word?” question arises. connection from the output to the Many singers without a lot of studio input. This is the standard recipe for experience, however, aren’t feedback. Start with the gain of the comfortable recording in this fed back (inverted) channels at manner. By taking advantage of the minimum and bring it up slowly. almost perfect null of a bi-directional Raise their gain too far and the microphone in the plane of the howling will start, but you’ll have diaphragm, it’s possible to position plenty of working range before that an LSD-2 so that the voice is in the happens. null of the instrument microphone and vice versa, allowing them to be Mastering the Shuffle recorded together without a lot of leakage. Equalizing the low end of the difference signal can sometimes Mount the LSD-2 so that it’s pointed save the day even when working horizontally and twist and turn the with a multitrack mix. If the tracks capsules aiming for the best have a lot of low frequency leakage, compromise between sound quality for example if the band was recorded and separation. You won’t get live and the bass is on everyone’s perfect isolation, but because the track, you can sometimes improve two microphones are very closely the apparent definition of the spaced, any leakage that you have instruments in the mix using this will be in phase, so bringing up the technique. It also can help to spread vocal won’t thin out the instrument or out a mix in which things have been vice versa, and with a combination of too crowded in the center. luck and careful placement, you can successfully do punch-ins on one of Many mastering engineers are the tracks without enough of the aware of this trick and it’s employed original part from the other track to by a few “mastering” software plug- be audible in the mix. ins, but you can Experiment with your microphone. It’s fun to hear all the different variations you can get with just a little tweaking here and there. Mic placement and technique is something that you really only learn by doing, but hopefully this guide will turn you on to some techniques that will prove useful in your work.