Mention ribbon mics to most engineers, and their first thought is “vintage mics from the 1940s and ’50s.” Their second thought is typically about how fragile ribbon mics are. Ribbon mics are iconic in our industry, as evidenced by their universal use as icons on audio buttons on computer software, but they are still valuable tools in an engineer’s tool kit in the 21st century, as well. Once you discover their unique sound and properties, you’ll be dismayed that you didn’t know about them earlier. I can speak from experience because I was 20 years into my recording career before Wes Dooley sent me a pair of AEA R84s to evaluate for a magazine review. It changed my life. I started adding ribbon mics to my mic collection and ultimately ended up with nearly two dozen ribbon mics.
In this article, I’ll share some things you might not know about ribbon mics and why you should always have at least one as part of your microphone arsenal.
Directionality
Ribbon mics are inherently bidirectional (figure-8), which means they pick up sound from the front and rear and reject sound coming from the sides. Mention a figure-8 pattern mic to engineers who are accustomed to working with cardioid mics, and they wince. “Why would you ever want sound coming in the back of the mic?” I’ll tell you why.
Uniformity
Though a cardioid mic grabs sound from the front and sides and rejects from the rear, it only partially rejects sound from the rear, and the sound from the sides and rear of the mic is extremely colored (meaning it sounds bad). A ribbon mic, by contrast, has a very uniform frequency response across the front of the mic and a nearly identical response across the back. As the sound level decreases when you get off-axis, it still sounds like the original source. And the sound pickup from the sides of the mic (90 degrees off-axis) is completely nonexistent. That’s because of the way a ribbon mic works. If the same sound pressure is present at the front and the rear of a ribbon, then it won’t move at all, meaning no sound.
Here’s an analogy: Think of it like blowing across a suspended sheet of paper. When you blow on the front or rear, the paper will move as a result of the pressure applied to one side. If you blow across the paper from the side, then the wind blows right past it without it moving because it’s the same pressure on both sides. That’s exactly how a ribbon mic works, but don’t blow on your ribbon mics! They are much more sensitive than a sheet of paper.
Side Rejection
One of the biggest advantages of a ribbon mic is how it completely rejects sound coming from the sides. This can be a godsend in many miking situations. If you have brass players (trumpet, trombone, tuba) sitting next to each other and want to maintain isolation between the parts, then a ribbon mic is ideal because the trumpet can be right next to the trombone and you will barely hear the sound of the trombone in the trumpet mic. Try doing that with a cardioid condenser! (Don’t bother. I tried it many times, and the bleed from a cardioid condenser is drastically worse.)
Or maybe you need a percussion mic that rejects the sound of everything else going on in the room. If you position a ribbon mic so that it’s parallel to the studio floor, then you’ll get the sound from below/above, but everything else that is in line with the mic (drums, guitar, singers) will be rejected. All you’ll hear is the reflections of those instruments from above and below.
Or you can use it on a singer who is playing acoustic guitar and point one ribbon at their voice and the other at the guitar, and you can record the guitar with little leakage from the voice and vice versa.
If you don’t understand what different polar patterns sound like, then check out the excellent audio demonstrations in this article: “Microphone Polar Patterns Demonstrated — Use Your Ears!“
Proximity
A great advantage of ribbon mics is being able to utilize the proximity effect, which means that low frequencies are boosted as you get closer to the mic. What you may not realize is how pronounced the proximity effect can be. The bass boost on an RCA 44 can extend up to four feet away from the mic. If you stand closer than four feet, then your voice or instrument will benefit from enhanced (often exaggerated) low-frequency boost. That’s why you can use ribbon mics and have them sound so full and natural even when the talent is farther away from the mic. Have you ever seen early black-and-white television music broadcasts where the singer’s voice sounds amazing with no mic in sight? Those typically used a ribbon mic that was on a huge boom arm up above the singer’s head, far enough away to be out of the camera’s view — sometimes five feet or more away. And the vocal not only sounds great, but the off-axis sounds of the orchestra and cameras are suppressed by the ribbon-mic pattern also.
And, when you use a ribbon mic really up close, like on a vocal or an electric guitar, you can get a huge, warm sound that other mics just can’t duplicate. That boost may be as much as 15dB or more, so it may be too much, but it can always be rolled off if needed. Or you can change the sound drastically by just moving the mic away a few inches.
Tonality
Have you ever listened to classic recordings of crooners and wondered how they got such a big, warm, but present vocal sound? Frequently, that sound came from ribbon mics. The same was true of early radio broadcasts. That huge, enveloping, “voice of God” sound? That was often a radio personality working up close on an RCA 77-DX. You can get that same sound by using a ribbon mic and working up close. If you have issues with plosives, then you’re likely working the mic too close.
A ribbon mic for vocals will sound very natural when working at a distance where most dynamics or condenser mics won’t. I’ve used ribbon mics (in a suitable recording space) on voice with the mic positioned 18–24 inches away from the vocalist. You can use it at eye level or move it up a foot or so to get the mic out of the singer’s line of sight. This works when you want the singer to emote and feel like they’re performing to a person instead of performing to a mic. It can be freeing when they’re not singing with their lips three inches away from a pop filter.
The other benefit of a ribbon on vocals is that they don’t have the spitty top end that many condenser mics exhibit. The natural high-frequency roll-off of a ribbon mic is something many people consider a detriment. But it’s really a great way to tame sibilance or a nasal-sounding singer. I used a ribbon mic on a very raspy male vocalist that sounded like sandpaper coming out of the speakers when he sang really loud. Using a ribbon mic and boosting the high frequencies to get a natural presence was perfect in this case. It kept his vocal sounding present and smoothed out the raspiness no matter how hard he sang.
Sonic Flexibility
It’s commonly understood by engineers in the know that ribbon mics “take EQ well.” Their flat, smooth frequency response means that they can take a lot of EQ without sounding bad. I’ve used ribbon mics and added 12dB of HF shelving at 6kHz, and they sounded perfectly natural. Don’t try that with most condenser microphones. You can also carve out a lot of low frequencies (think 6dB–10dB), and they still won’t sound thin. So, you can EQ until you find exactly what you want.
There you go. Four reasons you need a ribbon mic in your studio. Or, if you’re like me, you might need two. Or three. Or six. Or . . .
Call your Sweetwater Sales Engineer at (800) 222-4700 and ask them which ribbon mic will work best for you. And enjoy discovering a whole new tool that you never knew you needed.
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