Getting Sound Into and Out of Your Computer
Given the nature of what you’re going to be doing in your studio, getting sound into and out of your computer could be considered a pretty critical task! Many new computers provide a method for doing this right off the shelf: the computer’s audio interface. You might also hear the audio interface referred to as the sound card or the audio device. But whatever you call it (I’ll use the term audio interface), many new computers have one built right onto their motherboards. Unfortunately, while that audio interface didn’t cost you anything extra and it might do just fine for watching (and listening to) videos on YouTube, it’s typically far from up to the task of high-quality audio work, so you’re probably going to have to replace it. Let’s talk about some of the issues and options involved in this decision.
Built-In Audio Interfaces
As I said, many computers have an audio interface built into them. Typically, this audio interface is actually a part of the computer’s motherboard, so you can’t really remove it.
Such audio interfaces are nearly without exception low-quality devices that the computer manufacturer has included simply to give you a way to hear or record audio onto the machine as soon as you unpack it.
To see if your computer has an audio interface, look for the holes (called jacks) into which you’d plug headphones or a microphone. The Record jack is usually red, and the headphone/speaker jack is often green or black. On a tower machine, you’ll find these on either the back or the front of the machine and in some cases both. Figure 3.1 shows the jacks on the side of my laptop. Notice the little microphone and headphone icons next to the holes, which further identify their purpose.
Figure 3.1 Look for input and output jacks like the ones in this picture to see if your computer has an audio interface already.
We won’t be using built-in audio interfaces, but pointing out some of their limitations helps identify important areas to consider when choosing a different one, so I’ll spend a couple of paragraphs on some of those limitations.
Cheap audio devices typically have cheap components, such as their analog to digital/digital to analog (AD/DA) converters. AD/DA converters convert analog audio (such as the signal from your microphone) into digital audio that your computer can understand. Likewise they change the digital audio from your computer to analog signals that can play through your speakers.
These conversion points are absolutely critical to maintaining high quality, and that’s one place inferior devices fall flat. No matter how good your microphone is or your speakers are, if you pass a great signal through low-quality AD/DA converters, your audio quality suffers.
Low-quality AD/DA converters can be very noisy, and that noise ends up in your recordings or coming out of your speakers. You’ll usually hear this as a hissing sound in your recordings or the audio you play from your computer.
If you hear people talking about the signal-to-noise ratio, they’re talking about this issue (along with other issues that cause noise). Basically, you can think of signal-to-noise ratio as how loud the noise your equipment makes is compared to the volume of the desired material. Put your headphones on and listen without playing anything through your audio interface. The amount of hiss you hear is noise that your equipment is making and noise that will end up in your recordings. Obviously, you want as little of this as possible!
To record yourself playing all the parts on a recording, the ability to listen to something that you’ve already recorded as you play along and record something new is critical. Most of us know this process by the term overdubbing. The process revolutionized music recording back in the 1940s, with the main pioneer being Les Paul. (Yes, my guitarist friends, that Les Paul!)
For an audio interface to pull off this simultaneous play and record magic, it must be a full duplexing audio interface. In terms of audio interfaces, full duplexing simply means that the device can play audio and record audio simultaneously.
Another factor, latency, refers to the time it takes for audio to run through the AD/DA conversions that we discussed earlier. Let’s say you have your electronic keyboard’s audio outputs connected to your audio interface’s input jack. You press a key on the keyboard. It takes time for the audio to travel from the keyboard through the AD converter, through the software where it’s being recorded, back out the DA converter, and finally to your speakers so you can hear what you’re playing.
In other words, you never get instant feedback when you press that key. And if you’re playing a part along with something that’s already in your project, you don’t hear what you play at the same time you actually play it. Obviously, you can’t perform well like that!
Low-end audio interfaces will typically have unacceptably long latency; thus, even if they’re full duplexing, they would still be virtually unusable for multitracking due to the latency issue. High-end audio interfaces have much lower latency.
Here’s one area where you Mac users have the advantage over those of us who use the Windows operating system: The Mac operating system doesn’t suffer nearly as badly from the latency problems as Windows machines do.
As you saw in Figure 3.1, built-in audio interfaces typically have 1/8-inch mini jacks. You probably know that most professional musical gear uses cannon (XLR) connections or 1/4-inch connections. Of course, you can get converters and adapters, but with all the other drawbacks for these devices, why bother?
Also, you typically get only one input and one output from these devices (although some multimedia machines will have multiple outputs so you can connect a surround-sound speaker system). That’s limiting—especially on the input side—for anyone who wants to record two or more things at once. For instance, if you’re recording a drum kit and want 12 microphones (not unheard of at all, but I’ll show you how to avoid that nightmare later!), you’re way out of luck with the built-in audio interface.
High-Quality Audio Interfaces
All right, if you can’t use your computer’s built-in audio interface, what can you use? Luckily, there are several great options from manufacturers who’ve developed audio interfaces specifically for professional music production. And you have a few different options to consider. According to assumption 8 (which I stated in the introduction to the book), you don’t want me to dump a bunch of options on you and make you figure it out on your own, but there are a few times when I feel it’s necessary to give you more than one option so you can pick the one that most closely fits your situation. This is one of those times. I’ll try to keep the options straightforward so you can make a clear decision. Also, Appendix A, “Choosing Your Audio Interface,” helps you organize your thoughts in this potentially confusing area to help you determine what type of audio interface you should purchase.
Before we start, I should note that higher-quality audio interfaces solve all the problems that I discussed earlier.
There are three common ways you can connect a new audio interface to your computer.
As I mentioned earlier, a tower-style computer has more room to expand your computer’s functionality. Your computer’s motherboard typically has three or more expansion slots called Peripheral Component Interconnect (PCI) expansion slots. These are built specifically to accept peripheral devices that use the PCI standard connection and bring some extra functionality to your computer. We talked about software plug-ins earlier. Well, these devices could be considered hardware plug-ins because they literally plug right into the PCI slots. Devices like modems, video devices, TV tuner devices, network devices, and others might use the PCI standard to connect to your computer. Audio interfaces can also use this standard.
Most of the professional-quality PCI plug-in audio interfaces have another component called a breakout box. The PCI device sticks out of a hole in the back of your computer that is designed specifically for it. The breakout box connects to the PCI device via some sort of cable that also comes with the package. The breakout box serves as your connection interface to the audio interface and through that to the computer. In other words, the breakout box has the input and output jacks into which you plug your input sources (microphones, mixer, and so on) and your output destinations (such as speakers, headphones, and mixer).
Figure 3.2 shows a PCI audio interface along with its breakout box. Naturally, you’ll have to open your computer to install the PCI device. Make sure you follow the device’s instructions carefully so that you don’t damage your computer during the process.
Figure 3.2 This audio interface has three hardware components: the PCI device, the breakout box, and the cable that connects them.
Although I’ve had good luck with the PCI audio interfaces that I’ve used over the years, they’ve fallen out of favor with me due to a couple of factors. First, although they’re not really all that difficult to install, you do have to open your computer to do it. Once you do, that device is literally part of the computer, and it’s not very portable. If you want to use it on a different computer, you’ll have to open the box back up, remove the device, and then open the other computer to install the device there. Also, you obviously can’t install one of these into a laptop since laptops don’t have room for PCI slots and devices.
Another important negative I’ve found with the PCI devices that I’ve worked with involves the connections on the breakout box. For some reason, manufacturers only seem to supply 1/4-inch jacks for analog audio connections on these devices. That means that you can’t plug a standard XLR microphone cable into the device without first going through a mixer or some kind of adapter. Compared to FireWire and USB devices, these limitations were enough for me to lose my enthusiasm for PCI audio interfaces.
FireWire audio interfaces combine the audio interface and the breakout box into one unit that connects to your computer via an IEEE-1394 connection, known commonly as a FireWire connection. More and more new machines come with FireWire ports built in. If your computer doesn’t have a built-in FireWire port, you can buy inexpensive PCI devices with FireWire ports (many with two or even three ports on a single PCI device). Figure 3.3 shows a FireWire audio interface along with the FireWire cable that connects it to the computer.
Figure 3.3 This sound device connects to the computer via a convenient FireWire connection.
In my opinion, FireWire audio interfaces offer huge advantages. First, they’re completely portable. Since many computers have FireWire ports, you can easily unplug the device from one computer and plug it into a different computer. If you have a laptop with a FireWire port in it (as more and more of them do), you can easily plug the same FireWire audio interface that you use in your tower machine into your laptop.
Even more importantly in my opinion is the connectivity provided by high-quality FireWire audio interfaces. Many of these devices use handy combination input jacks that accept either a 1/4-inch plug or an XLR plug coming from a microphone. This way you can plug something like an electronic keyboard that uses 1/4-inch plugs into the audio interface when you need it but then remove it and plug a microphone directly into the device when you need that.
FireWire devices have other great features that I’ll talk more about later when we actually get to recording and working with audio.
Audio interfaces that use Universal Serial Bus (USB) connections have many of the same advantages and features as the FireWire devices I just discussed. The main difference is that they connect to one of your computer’s USB ports. If your computer doesn’t have a FireWire port, these devices are a great alternative because virtually every computer is built with a couple of these USB ports.
There are two types of USB: USB 1.1 and USB 2.0. USB audio interfaces generally require a USB 2.0 connection since USB 1.1 connections do not provide fast enough data transfer rates. Make sure that your computer’s USB ports are USB 2.0 if the audio interface you’re looking at requires that standard.
Regardless of the type of connection you choose, the audio interface you buy will come with its own software called drivers. The audio interface needs this software driver to communicate with your computer and DAW software. In reality, it’s the software drivers, not the hardware components that are likely to cause you the most problems with the audio interface. For that reason, it’s important to make sure you have the latest versions of the drivers for your operating system.
In fact, that’s true for any software you install. By the time you buy the software (or audio interface and software in this case) and unpack it at home, there have probably been a couple of updates to the driver software. Manufacturers almost without exception post these updated drivers for free download on their websites. A company puts out new drivers for good reasons; the driver update may fix bugs in the old driver, add functionality that the old driver didn’t have, or support a new operating system that the old one doesn’t support.
You need to seriously consider how many inputs and outputs you want your sound device to supply. You can find devices with 10 or more inputs and outputs (like those shown earlier in Figures 3.2 and 3.3) as well as devices with fewer. Most devices have at least two of each.
FireWire devices offer a great advantage here because, on some of them, you can string two or more devices together. For this to work, all the devices must use the same software drivers, which pretty much means they all have to be the same make and model. Stringing devices together like this gives you even more inputs. To do this, you plug the first one into the computer and the second one into a second FireWire port on the first one. The two devices strung together appear in your DAW software as if they were just one big device, and you can assign all those inputs to separate tracks in your DAW for recording simultaneously.
Give some thought to what you’re going to be doing with the device so you can determine how many ins and outs you need. If you’re going to record all the parts one by one, you might be perfectly happy with just one input. (Actually, most devices have a minimum of two mono audio inputs.) However, if you plan to record your whole band simultaneously with several microphones, you’re going to need more inputs. And if you want to play back out of the audio interface to a surround-sound speaker system, you’ll need more outputs.
Naturally, the more ins and outs your device features, the more you’ll pay for the device.
Also, make sure to consider whether you need MIDI input and output. We’ll talk much more about this issue in Chapter 7, “Utilizing MIDI in Your Projects.” For now, just keep in mind that most higher-end devices supply MIDI input and output jacks, while lower-priced devices may not. If you don’t know what MIDI is, hold off on your audio interface buying decision until you’ve read about it in the following chapter. Once you learn about MIDI technology, you may well want to make sure you buy an audio interface that features MIDI jacks.
Some manufacturers make audio interfaces that they combine with technology to create a multifunction piece of gear. For instance, the company Line 6 is famous for creating audio interfaces that also contain amplifier emulation technology. These devices enable you to plug directly into the audio interface and apply amplifier modeling sounds to the signal while you play or sing and record into your computer, thus eliminating the need for an actual guitar amplifier playing into a microphone or for a vocal preamp. Typically, these devices connect via USB.
Other devices combine the audio interface with a keyboard so that you always have a keyboard ready for transmitting and recording MIDI data. Still others combine the audio interface and a full hardware mixing console. In other words, there are a lot of options out there.
Such devices can provide great value, but be careful that you’re not limiting yourself too much. For instance, if you need to record vocals, make sure the audio interface easily supports a microphone, not just a guitar. And make sure that the interface provides output to your speakers and that it is a full-duplexing unit.