How to make NPR-quality podcasts at home
One of the main reasons I got hooked on NPR is the sound of it. It’s a close, intimate sound that makes you feel like you and the commentator are sitting together in a small room.
In fact, it’s an expensive microphone that’s sitting in the room with the commentator, and it’s recording his or her voice so well, you instantly feel that intimate connection. Three key ingredients help create the “NPR sound”: smart people with pleasing and distinctive voices, studio acoustics, and good mics and other audio equipment.
Podcasting shares a lot in common with broadcasting. Content is obviously the most important element, but people won’t listen to the content if the sound quality is bad. And they’ll listen longer and more often if the sound quality is really good.
I went on a quest to find out if it’s possible to achieve NPR-level sound quality in a podcast you make at home. Working under the premise that no one piece of gear could cost more than $1000, I set about trying to assemble the equipment I thought would give me the best chance of sounding like such names as Bob Edwards or Corey Flintoff.
I spent time in audio forums, reviewed the trade mags, and talked to audio engineers. I ended up choosing a set of products that form a chain starting at the microphone and ending at the software I used to record the sound.
I’m not suggesting that budding podcasters rush out and buy all the products I chose—that would run into some money. But the addition of any one of them, or something comparable, is enough to drastically improve the sound of your work. And building your arsenal of gear is a process: You upgrade as your interest, talent level, and budget grow.
The star of the lineup will be your microphone. It has a big job, and that’s why some of them command top dollar. They have to listen to the finest vibrations and details of your unique voice and tell an output device—in electrical impulses and then in digital ones and zeros—exactly how to recreate the sound.
Most of the microphones I tested for this story—the Shure SM7B, AKG Perception 220, Rode NT1-A, Neumann TLM 102, and Neumann TLM 103—are condenser microphones. In a condenser mic, sound levels affect the distance between two metal fabric plates, which translates into a varying electromagnetic current. The Shure SM7 is the one dynamic mic I tested. Dynamic mics contain a single diaphragm whose movements are translated into varying levels of electromagnetic current.
Your voice is unique, so what you're really listening for is the sound created by the combination of a certain mic and your particular voice. And the only way to determine that sound is by testing each mic for yourself.
Nonetheless, for each mic covered in this article, I'm including a sound clip of my own voice. This should help you identify some of the more objective qualities of each microphone, such as sound fidelity and noise levels. Try listening to the various recordings back to back, so you can hear the differences clearly.
I used iZotope’s Nectar 2 Production Suite sound processing package ($299) to apply a bit of compression, equalization, and de-essing to the recordings. The files were rendered from Pro Tools as lossless .aif files, but then (sadly) compressed further into MP3s.
AKG Perception 220
For comparison purposes, I included the $200 AKG Perception 220 in my tests to represent a whole class of consumer home studio mics. These mics are often purchased by people who are relatively new to home recording, and new to using condenser mics.
The 220 has decent sensitivity, and seems to be especially sensitive to higher frequency sounds. Because of that, I found it especially important to use my pop guard to filter out high-frequency “ess” sounds from the sound of my voice.
The mic’s output level is very low. I had to turn the True preamp (discussed later) almost all the way up to get to an optimum recording level.
The recordings I made with the 220 sounded more angular and less full-bodied than those made with the other mics in my tests. Perhaps worst of all, the 220 is a little noisy, meaning that it creates its own background sound that you can hear in the recordings.
Neumann TLM 103
I haven’t tried every microphone available, but I have used some very good ones in the professional recording studios I’ve worked in. In my experience, every legitimate recording studio has at least one expensive Neumann microphone that's used to record vocals. Take, for example, the vintage U47, which sells for up to $10,000 used (they’re not made anymore), or the U87, which sells for about $3600.
Neumann’s idea for the TLM 103 was to bring the qualities of those expensive microphones to a mic in the $1000 range. To my ear, the TLM 103 brings about 95 percent of the warmth, width, and accuracy of those more expensive Neumann microphones. Recordings of my voice were extremely clear, but I had to make sure I wasn’t getting too close to the mic: It’s so sensitive, it picks up unwanted lip smacking and saliva sounds. There’s such a thing as too much detail, indeed.
The only criticism I’ve heard about this mic is that it can bring a nasally sound to some people’s voices. I did hear hints of this in some of my recordings with the 103. But I didn’t find it to be anything that correct breathing and clear nasal passages couldn’t fix. You really can’t go wrong with this superior piece of German engineering. The real question is whether you can afford the $1000 price tag (though sometimes they appear for as low as $600 on eBay).
The Shure SM7B (about $350) is one of the best-kept secrets in the recording business. Actually, the mic has been a standard in the broadcasting world for a long time, but the music and home recording worlds are just catching on. Though it was designed as a broadcasting mic, Michael Jackson used it to record all the vocals on his Thriller record back in the 1980s. In audio recording forums, you can read stories about blind taste tests in which the SM7 easily beat out a lineup of high-end studio favorites like Neumanns and Sennheisers.
I’ve used the SM7B a few times in the recording studio, and based on the advice from my sound-engineer friends, I went out and bought one. The SM7B, for one reason or another, is great for recording spoken words, and I’ve found it to work very well for podcasting.
The SM7B made my voice sound big and bold in the recordings, a bit more so, perhaps, than the Neumann TLM 103 did. I believe that it lacks a little bit of the warmth and accuracy of the Neumann, but, honestly, I’m not sure I could have picked out that difference in a blind taste test.
The Rode NT1-A is a $300 microphone that’s considered by many to rival condenser mics that cost thousands of dollars. The NT1-A I used is more sensitive to high-frequency sounds than any other mic I’ve worked with. It’s especially well suited for recording stringed instruments like violins and guitars. But for many podcasting voices, it can produce warm and rich vocal sounds, provided that precautions are taken to control “essing.” For baritone voices like mine, the mic proved to reproduce the mids and mid-lows on the frequency scale very accurately and pleasingly.
Neumann TLM 102
After years of producing microphones solely for professional engineers in recording studios, the Berlin-based Neumann company decided to bring its well-respected name to the home recording crowd. The result was a small condenser mic called the $700 TLM 102.
After making a few recordings with the 102, it became obvious that the microphone does indeed have the clarity and rich sound reproduction of a Neumann. At the same time, I could hear a clear difference in the recordings made by the 102 versus recordings I made with its big brother, the TLM 103. I found that the 102 recordings lacked some of the bigness and richness of the recordings made with its older brother, the 103.
The TLM 102 is probably among the best microphones in its price range, but to my ear the low price tag comes at the expense of some of the qualities that make a Neumann sound like a Neumann.
The control experiment
For comparison purposes, I recorded the same podcast clip in a real recording studio using its fancy outboard preamps, compressors and A/D converters. The engineer set me up with an expensive Neumann U87 to speak into.
The result of the studio recording was about what I thought it would be. It sounds very good, and I wasn’t surprised. My voice sounds wide and full-bodied, but not in a “blunt instrument” sort of way. The recording seems to breathe, revealing some of the finer details of my voice and speaking style.
What I did find somewhat surprising, however, is how well my home recordings—especially the ones using the Neumann TLM 103 and the Shure SM7—stood up to the studio recording. While those mics didn't produce quite the level of warmth and expressiveness produced by the U87, they produced recordings that were almost as accurate, clean, and pleasing to the ear.
Your preamplifier amplifies the sound picked up by your microphone to a level that’s loud enough to be recorded by your recording software. It also supplies the mic with a small amount of power to send back its analog signal.
Lots of mic preamps are on the market, but it’s difficult to find one in the sub-$500 range that's powerful enough to produce the gain you need, and quiet enough that it doesn’t add its own noise to your recordings. The $600 True P-Solo preamp I used in my tests offers plenty of gain headroom to play with, and adds no discernible noise to recordings.
Many preamps do add their own flavor to the sound of the recording. Some have the kind of warm, punchy sound that can only be made by a tube preamp. Others create a fuzzy, vintage-y sound. Preamps like these—the Universal Audio 610, for example—can usually be found for $1500 and up. Choosing a preamp can be like choosing a microphone, in that you need to consider the kind of content you’re making, and the unique sound you're looking for.
For my podcasting purposes, I wanted a very clean and neutral-sounding preamp, and the True delivered just that.
The sound that comes out of the preamp is an electromagnetic analog signal. In order to record that sound in your recording software, it has to be converted into digital ones and zeros. That’s what your analog-to-digital (A/D) interface does, and there are potential pitfalls in this part of the chain, too.
Really good A/D converters create a digital representation of the sound of your voice that sounds exactly like the sound of your voice. And it’s crucial that the interface doesn't add any of its own noise to the sound.
I chose a great $650 product from Apogee called the Duet for iPad and Mac. It’s called the Duet because it can convert the sounds of two mics or instruments into digital at the same time, which is nice if you want to have a guest on your podcast. The Duet also has mic preamps built in, and I found that they worked very well with microphones that have reasonably high output. But because I was using the True as my preamp, I needed only the analog-to-digital converters in the Duet.
After the Duet converts the sound of your voice into digital, it sends the resulting zeros and ones to your computer via USB. I also used the Duet for monitoring: The device has a single headphone jack, and you control your volume using the big silver wheel on the Duet.
The Duet comes with a software product called Maestro that acts like a little mixing board for managing the gain of your microphones and monitoring levels. It’s also used to control certain functions of the Duet, like sending a 48-volt power source out to microphones that require it.
The Duet itself has LED gain meters for both microphones, for the monitor mix that goes out to speakers, and for your headphones. You can press the Duet’s big silver dial to cycle through those settings, turning the knob to adjust them.
About recording software
Ultimately, the sound of your voice is printed as ones and zeros on your hard drive. That digital information is managed and manipulated by your recording software, which is often called your DAW, or digital audio workstation. The best known of these, arguably, is Apple’s Garageband. For podcasting, it’s likely that Garageband has everything you need. The program makes editing your podcasts super easy, and provides a number of postproduction settings for compressing or removing hiss from your voice. You can also easily import music MP3s for the beginning or conclusion of your podcast—with sensitivity to copyright law, of course.
You can also look into specialized podcast products like Propaganda and ePodcast, which will help you with podcast-specific tasks like generating XML files or publishing directly to a website.
Preparing your recording space
Believe it or not, the acoustics of your recording space are probably even more important to the sound of your podcast than your mic and preamp. You can dramatically improve recordings made in your kitchen, den, or closet by improving the acoustics of the space.
Ideally, the space in which you record should be a dead space—that is, a space where most of the sound made by your mouth is caught by the microphone in front of you, and the rest is absorbed, not reflected, by the surfaces around you.
You can cover the hard surfaces in your space with foam tiles like Auralex to prevent them from deflecting sound. With $100 worth of this stuff, I was able to cover most of the walls above and around my microphone. Even if you don’t have enough foam to completely eliminate echo, it’s not hard to reduce it to acceptable levels.
Much of the echo that may be heard on a recording comes from the walls closest to the microphone. This echo can be defeated by placing the foam tiles a couple of feet above and below microphone level on the walls at the sides and in front of the mic. Some podcasters (and singers) have had great success by buying or building a concave foam panel that curves around the back of the mic at a distance of about a foot. This very quickly absorbs much of the sound coming from your mouth, and prevents it from bouncing back at the mic, causing echo.
The corners of the your space are particularly problematic for acoustics. Sound waves naturally move toward the corners of a room and can bounce off in all directions. The answer is something called a “bass trap”—a wedge-shaped piece of foam that effectively fills in the corner of a room and helps absorb the sound.
Foam is just one approach to deadening a space. Lots of other materials and methods exist—far too many for this article. You can read lots more about room acoustics and sound isolation here.
As a final note, YouTube videos can be your best friend if you get stuck and don’t know how to do something. Any problem you run into will probably have been encountered by someone else before you. You can find all kinds of hands-on gear reviews and how-to guides to help you with everything from microphone selection to speaking style to recording software tips and tricks.