Whether you’re gigging, recording, or just looking to be generally loud and annoying, microphones are an essential ingredient to anyone’s audio soup. But microphones aren’t all universal: in fact, they tend to be quite diverse in every area such as style, functionality, composition, and usage. It’s not uncommon to wade into the audio world not knowing one microphone from another. I’m speaking from experience of course: before I started working in a music shop, I had much more of a “pretty much anything will work for anything as long as I don’t break it or pour Gatorade on it” approach to mics. But these days, I’m a little older, a little wiser, and little…microphony…er…So I figure it’s time to walk anyone else who is willing to wade into the audio ocean through the transducy goodness of mics and their cousin-gadgets.
What’s a Transducer?
A couple of blogs back, I was ranting about pickups and made mention that in the electrical world, pickups are what is referred to as transducers. This basically means they are devices designed to take one sort of physical phenomenon (in this case, a physical vibration, a change in air pressure, or a sound wave) and convert it into a different physical phenomenon (an electrical signal), and visa-versa. Thus, microphones and loudspeakers are also transducers because you feed in one type of thing and, through the magic of ponies or friendship or something, it produces another thing.
Microphones and speakers, more or less, are actually the same thing, just backwards. They both deal with switching electrical signals to audible sounds and back again, making it possible to amplify and record music. I’ll talk in depth about loudspeakers in an upcoming blog, but for now I’d like to focus specifically on mics, starting with the basic anatomy of your average music microphone.
BEHOLD! The guts of a microphone!
In the plainest terms, you begin with a permanent magnet with a coil of wire (usually copper) wrapped around it placed behind a flexible diaphragm, all contained in some form of capsule or containment unit. When a vibration or a change in the air pressure (such as a singer’s voice or the sound waves from a guitar) acts upon the microphone, the internal diaphragm moves back and forth rapidly to produce disturbances in the magnetic field. These disturbances are then picked up by the coil in the form of an electrical charge and are sent down the wire towards the next destination (often an amplifier or a mixer) where the initial signal can then be amplified, altered, or what have you and then converted back to an audible signal. Uh, uh, oh, it’s maaagic!
Generally speaking, this is the way in which most microphones work in the music business. There are variations of the process and differing ways in how certain microphones acquire, alter, and function using the signals. What are those variations, you ask? We-hell, allow me to blabber you into a more thorough understanding!
As you may be able to infer from the name, dynamic mics function almost purely on the natural response from physical vibrations, with little to no added electrical components apart from the magnet and the coil itself: the electrical signal is simply produced from the basic dynamics of the diaphragm acting within the magnetic field. Chances are, if you are in a live-music scenario, most if not all the mics you’re using are dynamic mics (such as SM58 or SM57’s which tend to be the industry standard). Even in studio recordings, percussion, bass, and electric guitars are usually mic’d with dynamics.
Dynamics are advantageous for the musician or audio engineer in a number of ways; they are simpler than their buddies, the condenser mics, because they do not require any phantom power or internal battery power; they tend to be more robust and can take a better beating being more consistent despite environmental changes (weather, for example, or a rowdy, drunken audience member). They are relatively inexpensive to make, as well, since they are purely necessity-minded design.
Where they tend to be less advantageous, however, is also in their simplicity. Because the electrical signal’s strength is solely dependent on the physical work involved in moving the internal diaphragm, it goes without saying that it requires more effort from the initial signal source (the singer or the instrumentalist) to produce a strong signal than, say, a condenser mic (which we’ll talk about next). As a result, dynamic mics tend to have relatively low output level on their own and need to be amplified in some way. Also, they tend to have a weaker response to higher frequencies, which for the general rock and roll band in a live situation, isn’t a problem at all. But say you need a very meedley-meedly, demon-squealin’ metal solo recorded on the highest-fi money can buy?
You need something that can pick up the most accurate, precise signal to capture all that harmonic tastiness. A dynamic mic, unless dialed in to a T with the accuracy of a military sniper, probably won’t produce the signal you’re looking for. Your result will probably end up sounding muddy, distorted, and awfully noisy because of the gain required to fit the bill for a dynamic mic’s signal strength.
That’s why dynamics mics are ideal for live vocals, drums, bass, rhythm guitars, and anything else that doesn’t necessarily require super sensitivity to higher frequencies. To sum up, dynamic mics are the best choice when you are dealing with loud signal sources to begin with and when you need something that can withstand the wrath of a drummer who doesn’t know how to chill out.
But of course, the power of a dynamic mic is finite, just as physical phenomenon themselves are finite. But what if you added additional power to the whole debacle?
Also known as “capacitor mics”, condenser mics are kind of like the nerdy little brother of the dynamic mics; where a dynamic mic is like the jock kid who is stronger, tougher, though less efficient and a little simple, a condenser mic is like the fragile, efficient-minded prodigy kid with an asthma problem. Okay, not a great analogy.
Think of it this way (though the parallel isn’t perfect): if you recall the difference between active and passive pickups in a guitar, you can allow yourself to think of condenser mics and dynamic mics in the same way. Dynamic mics, like passive pickups, have a generally weaker signal though a more natural frequency response to the signal source; by the same token, condenser mics are similar to active pickups because of their added electrical power. A condenser mic works just like a dynamic mic in that it takes a physical signal and translates it into an electrical signal via diaphragms and magnets, but with two important differences:
Unlike a classic diaphragm mic, a condenser has two plates inside the capsule positioned within the magnetic field. One plate is fixed and the other is a ferromagnetic diaphragm. Both plates maintain a constant small electrical charge that is supplied by phantom power or an internal battery. When the diaphragm moves back and forth, the distance between it and the fixed plate varies, creating the electrical signal. The final result is a much stronger signal all on its own, and a much more accurate frequency response. In plain language, you get a lot more sound out of a condenser using a lot less work because of the added boost with the extra power.
Now of course, the stronger signal provided by the condenser mic is still small, so a condenser incorporates a built-in preamp system to bring the signal up to usable levels. This is one of the reasons the condenser makes are a little pricier than dynamics, and also a bit more fragile. There was a time twenty or thirty years ago when condenser mics were so dang fragile, a fly could land on the grill and blow the diaphragm up. Nowadays, modern material changes have made condensers significantly stronger, but because of their sensitivity to higher frequencies, they tend to be fragile by nature. They also tend to be a little more high-maintenance since they require additional power from either external (“phantom”) sources or internal battery sources to maintain the polarizing voltage in the two internal plates, and because of the way phantom power is supplied, all inputs in conjunction with a condenser mic have to be balanced.
The long and short of it is that condensers are ideal for accurate, precise frequency response. They can supply intricate signal from relatively weak signal sources, which make them useful for studio recording or much softer instrumentation. Another upshot is that condensers lend themselves to possible changes for the mic’s pickup pattern (where it picks up signal and how well), though most the cheaper models come cardioid style.
Which reminds me, before we get into ribbon mics and electret mics…
A Quick Note on Microphone Pick-up Patterns:
It stands to reason that different mics have different ways of picking up signal from the source. Here’s a quick breakdown on the more common types of microphone pick-up patterns:
Omni-directional pattern: these mics essentially pick-up signal from every direction at equal levels. The image depicts the signal “balloon” which, if you imagine the microphone itself in the center, is a characterization of where the microphone is getting its signal from.
Bi-directional pattern: or, a Figure-8 style pattern, receives sound signal at equal levels from both the front and back of the signal source. Classic ribbon mics are an example of Figure-8 pattern mics.
Cardioids (sub-, hyper-, super-): nicknamed for the vaguely heart-shaped signal balloon that it produces, cardioids mics are ideal for getting a good, balanced signal from the source. Most of the signal is picked up from the front of the source, but because it can still pickup background noises in the other directions (though at much lower levels), it maintains a better signal fidelity without making the desired signal sound flat or sterile (like it was recorded by a robot inside of a military bunker). These are very common pickup patterns for most things like vocals and instrumentation.
Shotgun Mics: though rarely ever used in the music world, shotgun mics are designed to be the most signal-specific. They gather most of the signal from precisely the source it is pointed at, and are ideal for very specific audio sourcing, like for film and television.
Now that we’ve got that covered, back to Ribbon mics!
Ribbon microphones, (or as they are known colloquially, “those shiny, fancy old-timey mics with the stuff and things”), are kind of an odd-duck style of microphone. The anatomy of the ribbon mic is unique. While a dynamic mic has a diaphragm that flexes in response to changes in sound pressure, a ribbon mic has a metal coil (or metal ribbon) placed between the poles of a magnet that, when vibrated, creates the disturbance in the magnetic field necessary to produce electrical signal.
As for the sound itself, ribbon mics are unusual. Though commonly much less efficient than other microphones due to output impedance and weak signal, they can produce surprisingly accurate and sensitive signal with higher frequency response, and when the signal strength is improved with additional power, can rival conventional condenser mics. Typically, though, they are quite fragile and aren’t commonly used outside of indoor situations. They tend to be bi-directional microphones, but some of them can be cardioid (or any of the other ‘oids) in specialty cases.
These days, most people seek out ribbon mics for the aesthetic and the “vintage” look. For those of us used to the industry standards and much more efficient design, they actually make dynamic mics with nearly identical innards as SM58’s and SM57’s in the style of a ribbon mics. They’re pretty cool. I got one for my mom for Christmas this last year and she was all over Facebook about it for weeks. We Hazen women like our faux-class gear.
Given the fact that most condenser mics aren’t very cheap, it can be hard for the starving artist in all of us (mmm…now I’m hungry) to get our hands on excellent quality microphones with the optimal frequency response possible. There was a time early on in the microphone world that condenser mics, while also still quite fragile and not nearly as idiot-proof as dynamics, mostly derived their large price tags from the more sophisticated innards that maintain the polarity charge in the plates. These, as discussed earlier, require some sort of external power source and therefore adds a buck or two to the whole shebang.
Then science (or the magic of friendship) gave us the wonderful idea of using electret internal components. “Electret” is actually just the bastard word of the two parent words “electrical” and “magnet”, and it is basically a term that means any sort of ferromagnetic material that can be induced with a permanent electrical charge, thus eliminating the need for an external power source to constantly maintain the voltage in the plates. Woohoo! Most still require some sort of preamplifier in the system of course, but the fact that the condenser mics have been simplified at least one step can actually save a lot of Benjamin’s from being kidnapped by the cash register (sorry, it’s hot today and my brain-parts are dumbing…) These days, most of the more affordable condenser mics are, in fact, electret mics and are pretty awesome for the money.
“So, Kellie…” you may be asking with your brow furrowed as such:
“When is the best time to use what mic? And also, how about you shamelessly plug some of what you guys have in your wonderful, fantastic store of yours that it totally awesome and everyone should shop at?”
Well, allow me…
From my own experience, I can say that the most important factor in choosing a vocal mic is the individuals voice itself and singing style. Often dynamic mics are preferred for live situations (or scenarios in which there will be a lot of variety at once) and either dynamic or condenser mics are effective in a recording scenario.
But keeping in mind that, like instrumentalist’s playing styles, everyone’s singing voice is different (strong, gallant, breathy, intimate, snarly, or just plain suckish). You may find a certain kind of mic suits your style better than another. Dynamics will suit a mid-to-stronger voice because the source is already quite loud and full itself, therefore providing a faithfully full and punchy signal. However, if you want to engage your inner Mazzy Star “help-I’m-about-to-faint-from-sheer-feminine-delicacy” type of singing, you might benefit from the accuracy and sensitivity of a condenser mic. Granted, there are no hard and fast rules for vocal mics in the sense that “this type is always better because yadda yadda yadda”. What matters is the end result, not so much the means.
That being said, here are some good recommendations for vocal mics here at the shop:
Peavey PVi100 ($29.99), PVi2 ($49.99), PVi3 ($64.99):
These are our “best-bang-for-your-buck” dynamic microphones, good for people who are exploring their options, who need a bunch of mics all at once without breaking the bank, or who just don’t need those fancy-shmancy city-boy mics. Each model gets a little nicer as the price gets a little higher, getting more deluxe with nicer features and accessories. Even the thirty-dollar PVi100 is a pretty amazing deal for the money, coming with everything it needs including a mic clip, cable, carrying case, etc. Rugged, easy to use, excellent quality, and easy on the wallet!
Shure SM58 ($99.99):
Probably considered the industry-standard for vocal mics, SM58’s are just downright awesome. Though certainly a step up in price, they pay for themselves very quickly. I can personally vouch that I’ve been utilizing the same four SM58’s for nearly a decade and a half now, and they just don’t quit. They’re built solid, have great frequency response, and sound excellent in every performance. After you’ve aged a decade or so and you’re still making the most out of your vocals with these guys, suddenly a hundred bucks doesn’t seem like much money.
Personally, I’ve found there only seems to be two kinds of drummers out there: drummers who want to mic EVERYTHING on their set, and drummers who could not care less about mic’ing anything and just want to play their friggin’ drums as loud as they can. Well, if you happen to be one of those “must-mic-it-all” drummers (or you’re not but you’re under the creative thumb of someone who requires you to do so), we’ve got some cool deals here at Bigfoot for you.
Stagg Condenser Mics ($83.99-$89.99)
I wonder if it is possible to have a crush on a rather anonymous manufacturing company, because if so, we definitely have a crush on Stagg. What I like about them is that they are able to sympathize with the average musician who wants good sounding stuff, but doesn’t want to waste time and money trying to hunt down super expensive, high-end stuff that may or may not deliver. Stagg’s microphones (along with all the other stuff they do, like electric violins and cymbals, for instance) are simple, rugged, awesome quality gear for hardly any skin off your nose (and by nose I mean wallet, and by skin I mean…leather?). Both models of condenser mics, the PGT-60 Studio Condenser and the CM-7050B Instrument Mic are awesome for the money, and for you drummers out there, they make killer overheads for your cymbals, hi-hats, and whatever other auxiliary percussion you’re making use of. Good news for drummers, because we’re the ones with all the expensive crap that takes up all the precious, precious space in our garages.
Samson C02 Pencil Condensers ($139.99):
Also a pretty awesome deal if you’re looking for some good overheads (or just really any sort of condenser mic whatsoever) is the C02 Pair Pack. Yep, you get two shiny, light-sabery pencil mics in a pack, and they are exceptionally good sounding microphones.
Samson 7Kit Drum Mic Set ($199.99)
Probably one of the best deals out there in the ways of condenser mics is the 7Kit Mic Set from Samson, which doesn’t just offer you seven studio-quality mics in one box, but it is also only sixty bucks more than just a pair of C02 overheads for the whole dang thing. You get three tom mics, a snare mic, a kick drum mic, and two overheads. That’s a well placed $200 if I ever saw one (second, of course, only to 200 tacos from your local fast food joint. Mmm…still hungry…)
Shure PG52 Drum Mic ($114.99)
This is for all the Bonzo disciples out there who need to get there heavy-handed kicks recorded at optimum rockitude. Being the sexy, rugged cardioids dynamic mic that it is, this thing will faithfully absorb all of your boot-heel aggression and give you some excellent, gut-shaking lows. Just be sure not to eat a big breakfast before sending that through your giant speakers with the reverb cranked.
For Everything Else:
As I previously mentioned, there are no hard and fast rules for mic usage, thought here are very handy guidelines to keep in mind so you don’t end up popping all the diaphragms or losing all the rock from mic to speaker. Here are a couple examples of all around great microphones that can do almost anything:
Shure SM57 ($99.99):
Like its sister microphone that SM58, these things are immortal as far as mics are concerned. It is a great example of the best of the tried and true, and an extremely versatile microphone that is not only awesome for electric guitar cabs, bass, drums, and whatever else you got, but they also make pretty sweet vocal mics all on their own if duty calls upon them. Fantastic dynamic mic that’ll give you the best of everything you need for either studio or live.
Shure Beta 57 ($139.99):
While the classic SM57 has maintained a time-tested repertoire for being one of the best all around mics out there, Shure has improved upon the original design by giving it an even more dialed-in pickup pattern and a noticeably higher output level. Slightly nicer frequency response and can be used for everything from vocals to drums to a drunken bag-piping monkey. And if that concept didn’t terrify me at the very thought, that’d be worth seeing.
C01U Studio Mic ($99.99):
This is a great microphone for studio recording, being that it is USB adaptable and comes with the Cakewalk® music production software. If you are interested in starting out with home recording and want to get the most out of a great microphone, this guy is a fantastic tool to start with and keep around throughout your varying projects.
Welp, that's about the gist of mics. There's a lot more I could talk about for this week, but I'm going to just ride out the heat wave with some hard cider and Halo. Have a good week!