What is an “audio interface” and which one should I buy?

Sat, 6 Feb 2010 11:42:02 -0800

If you are setting up a home music studio, there are a few pieces of essential gear you’ll need, but none of them are more important that an audio interface. An interface is the backbone of your studio, and these days it will not only determine the quality of the sound you are achieving, and how you make the most important connections in your studio, but it will also determine what audio software you are able to use on your computer.

WHAT IS AN AUDIO INTERFACE?
Some people get freaked out by the term “audio interface” but let me put your mind at ease and simplify the definition. Essentially, an interface is just a device (usually in the shape of a box) that allows the computer and the instrument(s) to talk to each other. This box converts the analog signal that you get from your instruments and voice (like a guitar, bass, or vocals) into a digital signal that your computer can read (for instance, USB or Firewire). This conversion process is sometimes summarized as A/D (which stands for analog to digital) or D/A (digital to analog) depending on which direction you are going. So if you’re shopping for an audio interface, you’ll likely see those abbreviated A/D or D/A terms used, and now you know what they mean.

WHERE DO I BEGIN?
If you are just getting started shopping for an interface, I know it can be overwhelming because there are a ton of companies on the market who manufacture them. In addition, they come in a wide variety of shapes and sizes, which can just make shopping harder. To help you start sifting through the sea of possibilities, I’ve supplied a list of my favorite, “recommended” manufactures on the right side. I encourage you to read the rest of this blog and then visit their websites to browse their interfaces and get an idea of what is out there.

WHICH ONE SHOULD I BUY?
These interfaces come in all shapes and sizes and have a variety of input and output jacks, preamps, and other connections built in, so deciding which one to buy is kind of like picking out a big-screen TV at Best Buy — you may be tempted to get a huge one with all kinds of bells and whistles on it, but ultimately you should get one that is an appropriate size for your living room (or studio), and make sure it has the right features and connections you need. Here are some factors you should take into consideration when deciding which interface is right for you.
• Software
If you already know what audio software to use (for instance Pro Tools or Logic), your choices for an interface may be narrowed down for you already. Some manufactures like Digidesign (who makes Pro Tools) have proprietary software that is sold and operated only with their interfaces. For example, if you want to use Pro Tools software, you will need a Digidesign or M-Audio (Pro Tools M-powered) interface. If you are using software such as GarageBand or Logic, you could use a variety of interfaces, but Apogee makes interfaces specifically designed to work on the Mac platform with those software programs. The important thing to realize here is that your software decision will influence your hardware (interface) options and vice versa. Check with the individual interface manufactures to see which audio software programs come with their interfaces (if any), or to find out which software programs are compatible with their hardware.
• USB or Firewire?
There are a large number of USB and firewire interfaces available on the market. Generally, the firewire interfaces have a faster/higher bandwidth than USB ones, which is good for recording multiple channels simultaneously. Firewire interfaces also tend to be a little more expensive or high end than the USB interfaces. The USB interfaces might not be able to host as many channels, but they tend to be more portable and universal, considering that not all computers have firewire jacks these days. If you don’t need a lot of channels, either type should do the trick. If you’re looking at more than 4 channels, I would recommend you consider a firewire interface.
• Inputs / Outputs
The inputs and outputs vary from interface to interface and can include 1/4 inch, XLR, SPIDIF, MIDI, optical, headphone outputs, and other types, so take a look at what connections you need in your studio before you buy one. If you are only recording yourself playing guitar and maybe singing, an interface with one or two inputs will likely do the trick. If you are planning on recording a full band simultaneously (with a guitar player, bassist, drummer, singer etc.) you will want an interface with more inputs so that you can record each instrument or singer on a separate channel. The key is to figure out the maximum number of channels you will want to record or use simultaneously, and get an interface that has at least that many inputs.
You’ll also want to consider what outputs you need. If you are simply dumping all your audio into your computer and only have headphones or a single pair of monitors hooked up, an interface with a headphone and stereo outputs should do the trick. If you want to send audio to other external devices (like a CD burner, effects processors, sampler etc.) you will want to have enough outputs so you can do that. Also, keep in mind that if you are running signals out to external gear, like an effects processor, you will want to make sure you have enough inputs to get the signal back into your interface.
• A/D & D/A Converters
The quality of A/D & D/A converters varies from one interface to another, and generally you get what you pay for. Figuring out what type of converters are included on an interface may require digging a little deeper into the manufacturer’s specs, but it is worth the investigation if you are concerned with the quality and “coloration” of the sound you will get out of the interface. Apogee, which is one of my favorite interface manufactures makes outstanding converters in their gear, and although they are expensive, I find they are worth the money. They tend to be very “neutral” and clear converters that don’t color the sound very much. Digidesign also makes nice converters, although I’ve heard some users mention that there is a slight high/mid bump in the resulting tone quality. I recommend you listen to different types — side by side if possible — to compare the differences and discover what works best for you.
• Sample Rate and Bit Depth Capacity
Finally, you should also consider the sample rates (44.1, 48, 96, 192kHz) and bit depths (16, 24) that your interface is able to handle. If you are only working on projects at home that don’t require professional quality audio, your standard 44.1kHz/16 bit should work just fine. If you are looking to work on higher quality audio, film projects, or record with higher sample rates, you may need an interface that can be set to work at higher settings (like 192kHz). Having the option to work at these higher settings can be beneficial, especially as you develop your recording skills, but the functionality will cost you extra when it comes to selecting an interface. To learn more about sample rates and bit depths, you may find this article helpful.

I hope you’ve found this blog helpful, and please feel free to chime in with a question or comment below.

- “The Notesmith”
Graham Pellettieri

How to record string instruments successfully

Wed, 12 Aug 2009 00:13:35 -0700

As both a violinist and recording engineer, I’ve spent a great deal of time testing out different techniques, equipment, and approaches for successfully recording string players. The problem is that stringed instruments are so dynamic, and each one has such unique timbres, they can be difficult to capture in an authentic manner when recording. Any recording engineer, or string player who has ever tried to record a stringed instrument, has probably experienced this difficulty before. Well, since people often ask me what the best approach is, I figured I would try and shed some light on the subject for those of you who are interested.

The short summary is that your recording technique and equipment of choice will ultimately depend upon what type of tone and sound you are going after. I’ll give you some basic directions for starting points, though, with the understanding that you should build upon that advice to fit your own needs.

Pickups vs. Mics: There are two main choices for recording stringed instruments: a pickup or a microphone, or even a blend of the two if you want to get fancy. In my experience, I’ve found pickups generate a nice, crisp attack and articulation on the notes, but can be somewhat flat and “velvety” when it comes to tone. This might be desirable if you are recording, say, fast fiddle music that has a lot of quick ornaments and accents that need to have “bite” to them. Getting a good balance over all four strings with a pickup usually requires the outside help of an EQ, though (whether that is on your amp or in your digital audio workstation [DAW]). Microphones, on the other hand, tend to capture more of the overtones and natural sound of the instrument. Their attack is not as pronounced, though, since the contact is more ambient and not direct with the instrument. You’ll also pick up surrounding noise with a mic (be it from another instrument or noisy street outside), whereas a pickup is more isolated. I prefer using microphones, because of their ability to capture the authentic timbre, but I recommend trying out both approaches if you haven’t ever experimented with them and see which one works better for your needs.

Mic choice and placement: If you decide to use a microphone, you’ll need to figure out, first, what type to use, and second, where to physically “place” it in relation to the instrument you are recording. Mics come in all shapes and sizes, and you can spend anywhere from a few bucks up to thousands, but it is important to know the difference in types before you go shopping. Generally there are two types of mics: dynamic microphones and condenser microphones. Dynamic mics are primarily used for live performance, and are not very “sensitive” in comparison to condenser mics. They are generally cheaper than condensers and can be used for recording, but I don’t recommend it. They won’t give you a large dynamic range, have narrow directional fields, and you have to get them uncomfortably close to the instrument to get a decent level. Condenser microphones are very sensitive and are primarily used for recording. There are large-diaphragm (good for cello and bass) and small-diaphragm (good for violin and viola) models, and they can be placed further away from the instrument and have wider directional fields. Note: condenser mics do require phantom power (48V) in order to work, so make sure your audio interface or mixer is able to supply that before you go out and buy one.

Now for placement. Assuming you’re using a condenser mic, you’ll want to have some space between the instrument and the microphone. For violin and viola players, I generally place a small-diaphragm mic above the player’s right side anywhere from 3-5 feet away from the f holes, and point the mic directly at them. (Violinists and violists can move a lot while they play, and their bows cover a wide range of motion, so make sure the mic and stand are comfortably out their way.) For cellists and bass players, I’ll place a large-diaphragm mic directly in front of the bridge, or slightly lower, anywhere from 1-2 feet away, and point the front of the diaphragm directly at the bridge. I recommend putting on a pair of headphones and having the player play while you listen to the recorded signal and adjust the mic placement to find the “sweet spot” where it sounds best.

Finally, if you’re getting into recording, you’ll need some other gear to complete the setup. You’ll want a DAW which these days is typically a computer with audio recording/editing software (i.e., Garage Band, Pro Tools, Logic, Ableton Live, Cakewalk, or Digital Performer to name but a few) and what’s called an “audio interface,” which is simply a box that converts the signal from analog to digital and vice versa. You’ll probably also want some monitors, headphones, mic stands and cables, too. If you are using good-quality microphones, it’s worth having a decent interface, otherwise you won’t be taking advantage of the mic’s full capabilities. As you get further into recording strings, you can start to experiment with plug-ins and effects like compression, reverb, chorus, and delay. You’ll quickly find it is easy to manipulate the sound once it has been recorded. Don’t be afraid to experiment with the whole process either—often the best tunes use creative or original techniques to achieve a desired sound.

- “The Notesmith”
Graham Pellettieri

Music Comes Alive Through the Art of Interpretation

Tue, 9 Jun 2009 00:04:06 -0700

Lately we’ve been working on producing three upcoming Strings Charts titles that will be published and released in the next few months. These range from string arrangements of rock originals to Latin-jazz standards to Eastern European dance music. As the music editor for the project, let me tell you that the process is both fascinating and enlightening! To help deliver a polished sheet-music product, part of our process involves proofreading the music with a group of fine, talented musicians—the Real Vocal String Quartet (rvsq.com).

At one point in the process, the group plays through the music proofs, while I check to make sure that the notation has conveyed the ideas of the composer or arranger to the fullest extent possible, and that the players are able to interpret those ideas clearly from what’s written on the page.

As it turns out, this proofing process is much easier said than done.

One of the charts in production is Grounded and Crazy in October: Rock Originals for String Quartet by composer, violinist, and producer Anna Stafford (annastafford.com). These two original compositions from Anna contain elements of many different musical styles—rock, pop, country, Eastern European, and classical to name a few. So defining the central stylistic focus of the book (and giving it a title to reflect that focus) was no easy task, but we felt that the rock elements in the music were predominant: hence the “Rock Originals” title. Anna’s recordings of the songs also provided a rock-oriented interpretation of the music, and we aimed to reflect that style in the notation. So imagine my surprise when the Real Vocal String Quartet played through the first tune and it sounded “Klezmer-ish” instead of rockin’! What the RVSQ latched onto in the music were the Klezmer-sounding elements, and the players used these as their foundation for musical interpretation. But Anna’s group had played the exact same music and made it sound like rock. How could this be?

It is because of interpretation.

The lesson I learned from the experience is that music can be written on the page with the utmost attention paid to articulation, text expressions, and specific notation, but ultimately the jump between what is on the page and what comes out of the instrument—the interpretation—is what truly defines music and gives it a style. You can give two people the same exact piece of sheet music, and they might play it totally differently simply because of their interpretations.

The experience has led me to look for ways to push the boundaries of music notation, and to try and find better ways to convey the composer’s ideas to the player, but it also makes me realize just how much of an art form playing music is. Ultimately, the musician—who uses artistic license while playing, and who executes his or her interpretation of the score—is an artist who brings the music to life and defines it.

Music lives in the art of interpretation.

I suppose that’s what makes playing music so much fun!

- “The Notesmith”
Graham Pellettieri

How Does One Successfully Program Contemporary Music?

Thu, 16 Apr 2009 23:52:59 -0700

These days, one of the biggest challenges facing the classical music industry is figuring out how to successfully program new music. It is no secret that concerts that only feature contemporary composers’ works and none of the traditional favorites—like Mozart and Beethoven—have a hard time filling the seats. So how do performing ensembles draw an audience to hear new music?

To find the answer, one needs to look no further than the Cypress String Quartet. Having the pleasure of attending the group’s 2009 Call and Response concert earlier this month in San Francisco, California, I witnessed the talented quartet draw a crowd of diverse youngsters to listen to the premiere of Lento Assai—a newly written piece by contemporary composer Kevin Puts (b. 1972). The secret to the quartet’s successful programming of contemporary music lies in its ingenious Call and Response program.

Now celebrating its tenth anniversary, Call and Response was designed to create new music that is based upon earlier compositions. Here’s how it works: each year, the Cypress Quartet selects two pieces from the standard quartet repertoire (the “calls”), and commissions a third work (the “response”) to be written by a contemporary composer. The commissioned piece is inspired by the two older works.

The program goes deeper than just the creation of new music, though. It even creates new audiences! Each year, the program offers several weeks of outreach presentations to students of all levels and backgrounds, and members of the community. Over the past ten years, Call and Response has reached over 16,890 students from middle and high schools around the San Francisco Bay Area. When all the presentations have been given, the program culminates in a public concert that features the premiere of the new work. With an average of around 500 attendants at each public concert, the audience is often as diverse as the music on the program!

The beauty of this Call and Response series is that it exposes younger generations to the new and exciting world of contemporary music. It helps them understand the significance of chamber music, and gives them insight into the process involved in creating new music.

So successfully programming new music is indeed possible, as the Cypress Quartet has demonstrated over the last decade, but figuring out how to do it yourself may require creating your own “response.

- “The Notesmith”
Graham Pellettieri

Videotaping practice sessions can be a revelation

Wed, 4 Mar 2009 23:43:46 -0800

When you’ve been playing violin for as long as I have (more than 22 years), you don’t expect to find any big surprises about your playing. At least that is what I thought until recently. Like many violinists, I’ve been through the gauntlet of classical training, had many teachers, and developed habits in my practicing over the years—some good, some bad. I’ve even done some teaching myself, but none of those things prepared me for what I recently discovered: I frown when I play!

And by frown, I mean that my facial expression when I’m concentrating (especially when reading music) is this sort of serious, tight-lipped, upside-down smile. This may sound funny at first, but it has a big impact on the listener’s perception of the music—it sucks joy and pleasure right out of the music and gives the performance an all-too-serious feel.

But let’s back up a minute. How could this be? After all, I’ve had plenty of teachers and played with many ensembles, but nobody ever mentioned anything about my “player’s face.” In retrospect, I realize that they all probably just figured that was how I looked when I played. Or maybe they thought that, since I was concentrating so hard, they shouldn’t mention it for fear of it becoming a distraction. Whatever the reason may be, throughout my entire playing career, nobody—teacher, colleague, or friend—ever mentioned my frown.

So how did I find out about it? All it took was recording a short video of me practicing vibrato the other day. Within a few minutes of watching the video, I realized that this frown was the single most important aspect of my playing that I needed to work on. I postponed my quest to improve my vibrato and set my sights on learning to smile.

I’d heard about the benefits of recording audio of your practice sessions. Some players will record the audio and listen back to it to get an objective perspective on their playing. It’s a great tool for improving your playing. You can focus on certain aspects (like vibrato, shifting, intonation, or rhythm) one at a time, instead of having to interpret them all at once as you do when you play. It can make a world of difference in how you hear yourself, and help illuminate what changes to make in your sound.

Given my background, I was no stranger to the world of audio recording. After all, I had played on albums, with bands, in the studio, and even recorded practice sessions occasionally—all of which gave me a reference for what my sound was like. But none of those recordings told me anything about how I looked when I played!

Now I understand that the visual messages you’re sending during a performance can be just as important, if not more so, than the audio signals.

Thankfully, with advances in technology, video is has become commonplace for musicians. I got a little Flip camera, so I could record videos of my performances and practice sessions. Let me tell you, these videos have given me a completely new perspective on how I should present myself on stage!

And while learning to smile and share some of the musical emotions though facial expressions were what I needed to work on more than anything, I found out other things about my playing, too. What I thought were dramatic sforzandos and big gestures while playing actually looked, and sounded, half as large when viewed from the audience. I’ve discovered that I need to exaggerate all my playing, emotions, and gestures even more to convey the appropriate energy levels.

And that’s just the tip of the iceberg. . . .

Try recording a video of your playing sometime. You may be surprised by the results and you may even find that you’ve got something to smile about.

- “The Notesmith”
Graham Pellettieri