Now it’s time to apply what we’ve learned and start to look at how to choose the right mic for your recordings. Right up front, before you can make any sort of decision about which mic you might want to use, you need to have a firm grasp of two things: the type of mics you have in your collection, and how each of them sounds.
But how to do that?
The first step—knowing the type of mics you have at your disposal—requires some homework, because dynamic, condenser, and ribbon designs perform differently. Your mics may also have different polar (pickup) patterns. And, they’ll likely have different feature sets (pads, low-frequency cuts, switchable polar patterns, etc.).
To acquaint yourself with each mic, either break out the documentation that came with it or browse the manufacturer’s website to learn all you can about that model. You don’t need to absorb all the tweaky spec stuff. Instead, it’s the features and functions that are important—you want to know what the mic does and how it works. It also helps to know the frequency response (for example, 80 kHz–22 kHz) and to look at the frequency-response graph— which will show you if there is a boost in a particular part of the frequency range or if the response rolls off the lows or highs.
To answer the second question—how does each mic sound?—you’re going to have to put in some studio time. When I get a new mic, I put it through a battery of test recordings: electric guitar, vocals, nylon- and steel-string acoustic guitars, hand percussion, and so on. First, I record all those sources with any switches on the mic off, then I’ll engage each switch to hear what difference it makes. This means switching on the pad, then the low-frequency cut, then changing the polar pattern, etc. Each switch affects the sound, and you need to know how.
If you have more than a couple of microphones, these sorts of test recordings get hard to manage. I like to create a separate Pro Tools session file on my computer for each type of test recording. I have two for electric guitar (one for clean and one for dirty tones), one for vocals, one for nylon-string, etc. As each new mic comes into my studio, I record its test tracks into the appropriate session. Over the years, I’ve accumulated a pretty nice selection of tracks highlighting each mic that I own or that I’ve reviewed or tested, and that allows me to compare each mic to the others.
Testing your mics and keeping sound files of these tests allows you to compare and evaluate each mic you own in the context of the others. It’s good to test a mic with a variety of sources—electric guitars, nylon- and steel-string acoustics, vocals, percussion, drums, and so on. Shown here are some sound files from my mic-testing collection. Careful labeling of the mic model, source, and switch settings is imperative.
To keep these sonic tests as consistent as possible, I play the same music (I load in a track I know well and play or sing along with it), and I take very careful notes so I can use the same mic positions and use the same mic preamps and settings. I don’t do any EQ’ing, compressing, or other processing.
The idea is to get a straight recording of each mic, so I can do easy A/B comparisons and really hear what each does. I also have similar Pro Tools sessions where I use the same mic, but switch out different preamps. You could also do one where you use the same mic and preamp, but change the mic position. Regardless of what you’re testing, you’re basically following the scientific method: Keep everything the same except for one thing you change for each test. This approach really lets you hear the difference that one change makes—or doesn’t make.
Once you’ve got your test tracks down on tape or hard drive, spend some time listening carefully to them. If you’ve got tracks for a few mics, do listening comparisons—this will require careful volume-level matching (a track that’s louder will always sound better to our ears than one that is quieter in a direct comparison), and it’s best if you can do such comparisons “blind” without knowing which mic you’re hearing. Have someone else switch the tracks behind your back so you can concentrate on what you’re hearing, not what you’re seeing.
The goal is to get a firmly grounded understanding of how your mics operate and a clear picture of their innate sonic characteristics. Once you have this knowledge, choosing the best mic for each situation becomes much easier. We never know exactly how a mic will sound until it’s in front of the guitar or amp, but at least these tests provide a good starting point for choosing the best mic for a particular application.
Next month, we’ll continue our discussion of how to choose the best mics to capture your tones. See you then! By the way, if you have suggestions for topics you’d like to see covered here or questions about any of my columns, drop me a line at firstname.lastname@example.org.
Mitch Gallagher is the former editor in chief of EQ magazine. He’s written more than 1000 articles and six books on recording and music technology, and has released an instructional DVD on mastering. His upcoming book is entitled Guitar Tone: Pursuing the Ultimate Electric Guitar Sound. To learn more, visit mitchgallagher.com.