A Beginner’s Guide to Macs and Mics

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A Beginner’s Guide to Macs and Mics

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Microphones 101: From Apple Pro
A Beginner’s Guide to Macs and Mics

By Joe Gore and Elise Malmberg

If you want to make recordings on your Mac, you need a microphone. But microphone choices can be bewildering. Options range from the tiny mic already inside your Mac to high-end models costing thousands of dollars.

This article surveys the various types of mics and audio interfaces to give you a sense of what to expect in terms of price/performance.

The $0.00 option. All Macs have a built-in microphone — it may be all you need if sound quality isn’t a big issue. For basic tasks like talking on iChat or capturing quick voice memos, the built-in mic works just fine. If your sole concern is basic intelligibility, you’re good to go. This is also a good first choice for the beginning podcaster. GarageBand’s Podcast studio feature includes speech enhancing technology, which will actually improve the sound quality of your speaking voice no matter what microphone you use.

The external mic upgrade. A decent external mic makes recordings sound fuller, clearer, and more detailed, with greater warmth and intelligibility. In other words, they’re nicer to listen to. The bare-bones tone of the built-in mic suffices for a brief memo, but it will fatigue the listener’s ear over the course of a 45-minute podcast. And if you plan to record anything musical, you’ll definitely want to go the external mic route.

But using an external mic adds another concern: how to get the sound from the mic to the computer.

Your Mac has a built-in input/converter: the 1/8-inch line-input mini-jack situated next to your headphone output jack. But it’s not the ultimate solution for great-sounding recordings. Like the built-in mic, it offers no-frills sound quality. And you can’t plug high-quality mics into this sort of jack. (There are plenty of budget mics that fit this jack, but their sound quality probably won’t be much better than that of the Mac’s built-in mic.)

Almost all professional mics employ a large three-pin XLR connector rather than a small phono plug. And it’s not just a matter of fitting the big plug into the small jack — you need a preamp to boost the low levels of microphone signals, and an analog-to-digital converter to translate the mic’s analog signal into digital data. Many mics also require an electrical power source to operate.

But don’t panic! Most audio interfaces do all those tasks — and more.


Audio interfaces — a PreSonus FireBox is pictured here — convert your mic’s analog signal into digital info your computer can understand. They can also improve the sound quality of your recordings and make the process faster and easier.

The audio interface advantage. Audio interfaces have XLR jacks for connecting mics, and USB or FireWire jacks for communicating with your computer. Even the simplest interface (like the no-frills models that sell for under $200) provide major upgrades in audio quality. They let you record at 24 bits, which sounds better than the 16-bit audio supported by Macs alone. They also minimize latency — the amount of time your computer needs to makes sense of sounds. With high latency, there’s a noticeable delay between what you hear in the room and what you hear back through your headphones. Latency isn’t much of an issue if you’re recording, say, a podcast voiceover — you’d just turn off your headphones while you speak. But if you plan to overdub multiple parts — for example, listening to a guitar part you just recorded while adding a second one — latency can be a serious problem.

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Most microphones and mic cables use a three-pin XLR connector. Photo by Joe Gore and Elise Malmberg.

What do you get when you spring for a higher-priced audio interface? Probably even better sound, thanks to superior preamplifiers. You might be able to record simultaneously via two, four, or more microphones, which is great if you’re trying to capture multiple musicians playing live, or several people speaking in an interview. Some interfaces include built-in effects, such as vocal reverb or simulations of electric guitar amplifiers. (So does recording software such as GarageBand and Logic Pro. The interface may offer specific sounds your software lacks, or free up CPU resources so you can run larger sessions.)


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Audio interfaces — a PreSonus FireBox is pictured here — convert your mic’s analog signal into digital info your computer can understand. They can also improve the sound quality of your recordings and make the process faster and easier.

Microphone Types
Different types of mics convert sound into an electrical signal in different ways, each with unique benefits and drawbacks. All microphones “color” the sound of whatever is being miked. Sometimes this coloration is undesirable or even unpleasant. In other cases, it actually enhances the sound — depending upon the microphone, it may add warmth, smoothness, or a commanding “edge” to the tone.

The two most common types are dynamic and condenser mics. In general, dynamic mics are less expensive and more durable. Condensers cost more and must be handled with greater care, but can deliver greater dynamic range and detail.

Pickup patterns. Microphones are also classified according to their pickup (or polarity) pattern. This describes the way the mic “hears” the sounds around it. The most common patterns are cardioid (heart-shaped), bidirectional (figure-eight), and omnidirectional. Some higher-end mics allow you to switch between patterns for different recording tasks.

If you’re only buying one mic, a cardioid pattern is your best bet. A cardioid mic picks up sound directly in front of it and rejects sound to the rear and sides, which makes it especially useful for miking vocals, solo instruments, and amplifiers. For vocalists singing with a live band, a cardioid pickup pattern is ideal — it maximizes the vocal signal while reducing interference from other instruments, monitor speakers, and crowd noise. In contrast, an omnidirectional microphone is good for capturing everything that’s said at a conference table, as it picks up sound equally from every direction. A bidirectional mic picks up sound equally from the front and back.


Dynamic mics are inexpensive and nearly indestructible.

Dynamic microphones. Dynamic mics can capture loud sounds without distortion, which makes them useful for projecting vocals over a band, or miking drums or guitar amps. When used properly, they can add “presence” or “edge” to the sounds they pick up. They’re built for the physical demands of live performance, so they’re less likely to break than other microphones. A good general-purpose dynamic mic, like the classic Shure SM58, starts at around $100.

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Dynamic mics are inexpensive and nearly indestructible.

But dynamic microphones aren’t perfect for every purpose. They capture less detail and fidelity than some other microphone types, so you might want to choose a different microphone type to record acoustic guitar, acoustic piano, or a solo vocal track. But some big rock stars choose dynamic mics to record vocals even though they could use a “better” microphone, because they prefer the power, edge, and attitude that dynamic mics can deliver.

Condenser microphones. Condenser microphones are commonly used for music recording, especially on vocals and instruments such as acoustic guitar or piano. A good condenser mic can pick up much more tonal variation and nuance than most dynamic microphones. But they also tend to cost more and are more fragile. Because they pick up more sonic detail than dynamic mics, condensers require special handling — you’ll probably want to learn a bit about microphone setup and technique before using a condenser to record vocals.
Small-diaphragm condensers are often used on instruments like percussion, acoustic guitar, and acoustic piano, because they respond well to instruments with sharp, snappy attacks. Large-diaphragm condensers are more frequently used on vocals and instruments without sharp attacks, like strings. Small-diaphragm models are generally less expensive than larger-diaphragm models.

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Condenser mics — a Blue Bluebird microphone is shown here — usually offer the greatest sound quality, but they’re more delicate and expensive than dynamic models.

Though condenser mics are available for as little as $35, you’ll probably need to spend more for a mic that delivers professional-sounding results. The small-diaphragm Sennheiser e914 ($350) is designed for recording instruments like percussion and acoustic guitar, while the large-diaphragm Blue Bluebird ($500) is a good all-around mic that also works well on vocals. Other popular condensers used to record vocals and other instruments include the Audio-Technica 4050 ($600), AKG C-414 ($1,000), and Neumann TLM-103 ($1,000). Prices can go up to several thousand dollars for some other condensers.

Other Microphone Types
Ribbon mics offer much more sensitive response than dynamic mics, and can add smoothness and warmth to digital recordings. But they are also fragile and pricey. (For example, the Royer R-121 Dynamic Ribbon Microphone sells for $1,300.)

Lavaliers (or lavalieres) are the mics you see clipped to the lapels of newscasters or talk show guests. They work much like condenser microphones, but they do not offer the same level of clarity and detail. Lavaliers are useful for spoken word applications like interviews or discussion panels. Wireless models are sometimes used to record location dialog for video productions. Lavalier mics cost from $75 for a basic wired mic to $200 or more for a wireless system with transmitter.

A PZM (pressure zone) mic, also known as a boundary microphone, is a unique type of condenser microphone. The microphone capsule is mounted on a flat plate that reflects sound into the capsule. Typically, a PZM mic is placed flat on a table or floor to pick up all the sounds from a large area, as opposed to a single voice or instrument. Prices range from $70 to $320.

USB mics are recent innovations. These mics feature a built-in analog-to-digital converter and preamp, so they can be plugged directly into your Mac’s USB port, eliminating the need for an additional interface. Most USB mics are condensers ranging in price from $80 to $160, though Sampson also makes a dynamic USB mic, the Q1U ($50). To minimize noise, USB cables must be kept short (usually ten feet or less) compared with regular mic cables. The better USB condenser mics offer low latency and a clear, uncolored sound. While many of the low-cost USB microphones might not match the sound quality of a higher-end condenser microphone for music recording, they may be a good choice for podcasting or basic voiceovers.
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Re: A Beginner’s Guide to Macs and Mics

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What differences can you expect between recordings made with your Mac’s built-in mic, with a modest dynamic mic and preamp setup, and a higher-end condenser mic and preamp? Hear for yourself.

Example 1) Here’s a recording of a nice acoustic guitar made via the Mac’s built-in mic. It’s noisy and less sweet-sounding than it could be.

Example 2) Here’s the same guitar through a popular dynamic mic and an inexpensive audio interface. Big improvement

Example 3) Finally, here’s the guitar through a pro-quality condenser mic and preamp. It sounds more like what you’d expect to hear on a big-budget recording.
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