In this dual-mic setup, an Audix i5 cardioid dynamic is positioned against the amp grille,
pointed at the edge of the 12" speaker cone. A Cascade Fathead ribbon mic sits about 2' back to
pick up room tones with its figure-8 polar pattern. Photo by Andy Ellis
In most recording situations, mic’ing up a guitar amp speaker follows a fairly standard procedure—choose the mic, jam it up to the speaker, and move it around a bit until you find a tone that works (or at least one that can be equalized into submission). There are benefits to this approach, which is why so many guitar tracks are recorded this way. The advantages are:
- It’s relatively easy to find a good location for the microphone.
- If you take decent notes and measurements, and draw a diagram or take a photo, it’s a simple matter to repeat the placement for sonic consistency in future sessions.
- Close mic’ing provides good isolation. With the mic right up on the speaker, you’re not in danger of getting much bleed if there are other instruments being recorded at the same time.
- It provides a robust, rich signal. No worries about getting solid levels, the mic is right there at speaker central!
- With a directional mic, such as a cardioid, putting the mic up close lets you take advantage of the proximity effect for a thick, full bass response.
- You get a very dry sound with no room influence or ambience, making it easy to EQ. This way, you can choose to add whatever reverb or delay you want later.
One solution to these downsides is to pull the mic back from the speaker a bit. Even a few inches can make a huge difference in the “naturalness” of the tone and the depth the mic captures. Pull the mic back a foot or more, and you’ll find the natural ambience of the room just becoming audible in the track. Move the mic back even farther and the tone may become even more “roomy” or ambient, or distant- sounding—possibly more distant than you want.
The problem is, if you record the track with too much room, you can’t really go back and fix it later. Plus, if you add EQ to a guitar tone recorded with room ambience, remember that you’re adding the same EQ to the room ambience as you do the guitar, which may make the ambience sound odd. Adding reverb or delay to a track that already has room ambience on it can result in a mushy, muddy, congested-sounding mess—losing the true ambiance of the room.
As a solution, it seems as if we want the best of two worlds. The ideal in many cases is to gain the control and isolation of a close-mic’d tone along with the depth, richness, and roomy natural vibe of a sound source mic’d at a bit of a distance. It’s pretty much impossible to achieve all of that with one microphone—so the trick is to use two mics, one placed close up on the speaker and the second pulled back into the room.
If you have a good idea of the final sound you want, you could mix the mics as they’re being recorded and lay them down to one track at the same time. But most engineers prefer to record each microphone to its own track. That way, you can EQ them separately, compress the close mic if necessary, and add any reverb or delay to each track individually. With each mic on its own track, you’ll have maximum control and flexibility during mixdown.
That’s it for this month. If you’ve never tried recording a distant mic along with a close mic on your amp, your homework is to give it a try. Next time around, we’ll continue our exploration of how to capture great guitar tones using more than one microphone.
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.