A microphone may be the most critical component that you buy. If you’re a singer or want to record almost any acoustic instrument (guitar, piano, flute, and so on), you need a microphone, and the quality of your recording will be greatly influenced by your choice of mic.
My Webster’s Concise Electronic Dictionary defines a microphone as “an instrument for transmitting or recording sound by changing sound waves into variations of an electric current.” Technically, that’s not a bad definition, but I prefer a simpler one: “A device that captures incoming sound and saves it (as a tape recorder or GarageBand does) or transmits it (as a telephone or walkie-talkie does).”
Musicians and audio enthusiasts often refer to a microphone as a mic, (pronounced “mike”).
If your Mac has a built-in microphone or an audio-input jack or both, you can use the built-in mic or connect a cheap mic to the audio-in jack and make some recordings. If they sound good to you, you just saved yourself a lot of money; if they don’t sound good, buy or borrow a better microphone and re-record the material. Now compare the two recordings and decide whether the better mic is worth the money.
Microphones vary greatly in price and quality. You can pay as little as $10–$20 for an inexpensive, consumer-quality mic on Amazon.com or at your local Best Buy, or you can spend thousands of dollars for a pro-quality mic at your local or virtual pro audio dealer.When it comes to microphones, price and sound quality don’t necessarily correlate directly. You can find inexpensive microphones that sound as good as (or better than) other microphones that cost even ten times as much. However, you generally get what you pay for, and more expensive microphones usually sound better.
The main things to consider when choosing microphones follow:
- Type of mic (dynamic, condenser, or ribbon)
- Polarity pattern (cardioid, omni-directional, figure-8, and so on)
- Connection to your device (usually USB, XLR, or both)
- Preamps
- Price (of course)
Dynamic and condenser microphones
Many types of microphones are available, and they use different mechanisms and electronic components. The two types that you’re most likely to encounter, though, are dynamic and condenser microphones. The technical differences in the way that each type works aren’t important (at least not in this article), but you should know the following nontechnical differences between the two before you consider choosing one kind (or both):- Dynamic mics are generally less expensive than condenser types.
- Condenser mics generally reproduce vocals and acoustic instruments more accurately and with more warmth. (Warmth is a desirable tonal characteristic that might best be described as mellow or not bright. It refers to a pleasant decrease in mid and mid-to-high frequencies that make a voice or instrument sound smoother when recorded.)
- Dynamic mics can be placed closer to loud bursts of sound — such as drums or a guitar amp — than condenser mics, so dynamic mics may achieve a sound that you just can’t get with a condenser mic. Furthermore, a condenser mic is more likely to be damaged by extremely loud sounds than a dynamic mic.
- Many dynamic mics are built for rough use — they better withstand being dropped on the floor or being knocked over with a mic stand. If you’re rough on your gear or plan to use it in a live stage setting, a dynamic mic will probably last longer.
- Condenser mics require a power source (known as phantom power), so they must contain an internal battery or have the phantom power supplied through the cable by your audio interface or mixer.
Not all audio interfaces and mixers supply phantom power to condenser mics. If you plan to use one of these mics, make sure that the device you’re going to connect it to — for example, an audio interface, a mixer, or a sound card — provides phantom power for it.
A third type of microphone — the ribbon mic — is fragile and expensive ($1,000 and up). And although ribbon mics are prized for a silky response, they don’t sound that different from condenser mics. You probably want to avoid ribbon mics unless you’re a purist and have deep pockets. I recorded with a ribbon mic in a studio many years ago, and it did indeed sound silky. So does the Neumann U87 (around $3,600), still the gold standard for condenser mics.
If you buy only one microphone, you can’t go wrong with a dynamic mic such as the Shure SM57 or SM58. These are two of the most popular dynamic mics around @@md and have been ubiquitous standards for modern live vocals since their releases nearly half a century ago.The SM57 and SM58 are similar, but the SM57 has “contoured frequency response for clean sound reproduction of amplified and acoustic instruments,” whereas the SM58 is “tuned to accentuate the warmth and clarity of lead and back-up vocals.” The SM58 is the ball-shaped mic you see all the time on stage and in videos.
The differences between the SM57 and SM58 are small and you may not even be able to hear them. Either is fine for both vocals and instruments. If you’re buying only one, decide whether recording vocals or recording instruments is more important, and choose accordingly. You can buy either one from online music vendors such as Sweetwater Sound and Musician’s Friend for under $100.
Microphone polarity patterns
Each microphone is designed with a specific polarity pattern, which means they pick up sound from certain locations better than others. The three polarity patterns you’re most likely to encounter follow:- Cardioid (directional): Cardioid mics, as you can see in the following figure, reject sound from the rear and sides, making them excellent for recording an instrument or a vocal with little or no extraneous sound leakage.
Cardioid patterns come in three flavors: cardioid (left), super cardioid (middle), and hyper cardioid (right).- Omni-directional: Omni-directional mics pick up sound from all directions equally, as you can see in the following figure. That feature makes them a fine choice for recording a large ensemble or orchestra but not the best choice for recording individual voices and instruments, which is what you do in GarageBand most of the time.
The omni-directional pattern picks up sounds from every direction.- Figure-8 (bi-directional): Figure-8, or bi-directional, mics pick up sound from the front and back equally while rejecting sound coming from either side, as shown.
The figure-8 pattern is perfect for recording two instruments or vocalists.The preceding figures are polar graphs that show how well the mic picks up sound from the front, rear, and sides. The specification sheets for most microphones will include a polar graph of its polarity pattern.
The three flavors of cardioid are so similar that you won’t notice much (if any) difference between them for the kind of recording you’re likely to do when working with GarageBand. I merely include this information so you won’t be confused when you start seeing these terms in brochures and reviews.
Finally, my favorite mic at the time of this writing is a Blue Yeti Pro, a great sounding condenser mic with both USB and XLR connectors as well as four polarity patterns. It’s not cheap, at around $250, but it has been superb for almost everything I’ve recorded with it.Microphone preamps
You have one last thing to consider if you’re buying a microphone: Your mic preamps have a tremendous effect on how your mic will sound.A mic preamp amplifies the sound coming out of the microphone to the higher voltage known as line level. Mixers, tape recorders, GarageBand, and almost anything else you might use a decent microphone with require line level input for recording.
If your microphone plugs directly into the Mac’s audio-in port or your iDevice’s Lightning port, you’re using built-in audio preamps, which are lower quality than most outboard gear but good enough for GarageBand work in a pinch.If you purchase an external audio interface, chances are it will tout its own preamp circuits; all of these will provide a cleaner signal than your Mac or iDevice’s built-in audio-in subsystem. Usually (but not always), more expensive interfaces offer higher-quality preamps.
Set up your microphone
Many Macs and older iDevices have a built-in microphone or an audio-input jack or both. A built-in mic requires no extra work on your part. If you have just an audio-in jack, you may be able to simply connect a cheap mic to it and make some recordings.However, most quality microphones (dynamic and condenser) as well as many other pieces of audio gear you’re likely to encounter use cables with XLR connectors. Because no Mac or iDevice has built-in XLR ports, you can’t plug an XLR cable directly into a Mac or an iDevice. If you choose a microphone with an XLR connector, you also need an audio interface (or an internal sound card), a mixer, or another device that has XLR inputs. This device sends its output to your Mac through one of its built-in ports, such as USB, PCI (Power Macs only), or Lightning.