The person behind the camera matters more than the camera. The same applies to making great audio recordings—the person behind the gear matters more than the gear. This doesn't mean that the gear doesn't matter, because it does. But merely owning the most expensive, elite audio equipment won't turn you into Tom Dowd or Rick Rubin or Quincy Jones or George Martin or whoever your favorite legendary music producer is. It won't turn average musicians into stars.
When you're shopping for audio gear and getting drawn into the “higher specs and price tags is better!" zone, take a step back and reboot your mind. Take a deep breath, slow down, and concentrate on learning how to get the best out of lower-end equipment. Because today's average digital audio gear is better than the top-of-the-line analog studio gear of yesteryear, with more accuracy, fidelity, wider dynamic range, and less noise, it's a whole lot easier to record, mix, edit, and apply special effects. You won't have to fuss so much with learning how to use your equipment, and you can concentrate more on learning how to make good recordings with artistic and technical fidelity. Then if you find yourself yearning for a better preamp, better microphones, better speakers, or what-have-you, you'll have good reasons, and you'll know and appreciate better quality when you find it. In this chapter we're going to turn a PC into a digital audio workstation, and we won't break the bank to do it. We'll also look at portable digital recorders, which cram amazing fidelity and storage capacity into tiny devices and are endlessly useful in all kinds of circumstances.
Getting Sound In and Out of the Computer
One of the biggest hurdles with PC-based audio production is figuring out audio gear. There is a huge and bewildering selection of audio components with every imaginable combination of features and price tags. In this chapter I'll discuss the basic elements of a small recording studio. Appendix A goes into more detail on hardware, with examples of different models and brands in different price ranges.
There are several ways to interface audio gear with a computer: a PCI or PCI-E sound card for a desktop computer; a Cardbus or ExpressCard sound card for laptops; USB 1.1, USB 2.0, or FireWire audio interface for any computer. You will need one of these. Which one? For one- or two-track recording, any of them will do. For heavy-duty multitrack recording, USB 1.1 is not a candidate. But it's great for one- and two-track recording, and you'll have a lot of excellent, moderately priced devices to choose from. For serious multitrack recording, you need the faster protocols, especially if you're going to record at high bit depths and sampling rates, so we'll look at their strengths and weaknesses.
The most essential component in digital audio production is the analogto-digital/digital-to-analog converter. The ADC/DAC is how you get analog audio in and out of your computer. It takes the analog signal from a microphone or instrument and converts it to a digital signal. Then it converts a digital signal to analog for playback. ADC/DACs come in a multitude of forms: The most low-end, cheapskate onboard sound chip has one, and of course so do higher-end audio interfaces. There are all kinds of USB and FireWire recording interfaces that connect microphones and instruments to your computer, and with them you don't need to bother with an internal sound card at all. There are also slick little portable ADC/DACs for connecting turntables, cassette recorders, and stereo hi-fi amplifiers to a computer, as well as USB microphones and turntables with built-in USB ADC/DACs. And for the studio geek with a healthy budget, there are the more expensive rack-mount ADC/DACs.
An Example Studio
Let's start off with a photo of a basic, moderate-quality computer recording studio, which just happens to be mine all mine. Figure 2-1 shows the whole works: The computer is underneath the table. Starting from the left are various headphones; then on the desk is an external USB CD/DVD writer, a four-port powered USB hub, an LCD monitor, a color printer, the allimportant hot beverage mug, a turntable, an excellent old Pioneer stereo hi-fi amplifier, a Behringer powered mixer, and a MobilePre USB preamp/ analog-to-digital converter. In front are two dynamic microphones. Not shown are a pair of nice JBL speakers mounted up on the wall. You can cram a lot of functionality into a small space.
Figure 2-1: My own little recording empire (the mics don't really sit right there in front of the amp and mixer; that's a pose just for the photo op)
Also not shown is a nice Focusrite Saffire Pro 26 I/O FireWire multichannel recording interface. Focusrite makes great audio hardware and supports Linux, Mac, and Windows. We'll see more of the Saffire in Chapter 9. This is how they all fit together:
- Recording: microphones and instruments > Behringer mixer >MobilePre > computer
- Playback: computer > MobilePre > Pioneer stereo amp > speakers
For recording, the Behringer mixer has a pair of RCA recording outputs. These send a stereo signal via an RCA-pair-to-two-1/4" mono TRS adapter to the two 1/40" TRS jacks on the MobilePre. The MobilePre connects with a USB cable to the computer. Everything plugged into the Behringer is then
captured in Audacity.
NOTE: The terminology for connectors is a bit mixed up, so I am going to refer to the connectors on cables as plugs and the sockets on mixers, preamps, amps, and so forth that they plug into as jacks. I will also bow to convention and refer to male and female connectors even though that has always sounded weird to me. Male and female at least have the virtue of having precise meanings, unlike a lot of audio terminology.
For playback, the MobilePre has a 1/8" stereo output. This connects with a stereo-mini-plug-to-RCA-pair adapter to the Aux input on the Pioneer amp. The MobilePre also has a pair of 1/4" TRS outputs, so for these I would need 1/4"TRS-to-RCA adapters. Figure 2-2 shows the plug-ins on the back of the amp. A nice amp like this plus a good ADC/DAC makes a great hub for a conversion studio, because anything that connects to the amp can be recorded on your computer.
Figure 2-2: This is the back of a treasured old but versatile Pioneer stereo amplifier. It can connect two turntables (it even has proper ground connectors for turntables), two tape decks, a microphone, a tuner, another amp, a preamp, and an Aux connector for a CD player or other input devices.
I could also cut out the Behringer entirely, for example for interviews and podcasts, and use only the MobilePre in combination with any computer.
When I'm copying vinyl LPs to CD, it goes like this:
- Recording: turntable > Pioneer amp > MobilePre > computer
- Playback: computer > MobilePre > Pioneer amp > speakers
The turntable plugs into the phono ports on the amp. The amp connects to the MobilePre from a pair of recording outputs. I could use an RCA-pair-to-two-1/4" TRS adapter or an RCA-pair-to-stereo-mini-plug, because the MobilePre is flexible when it comes to making connections.
You can digitize any legacy media with this kind of setup, because whatever connects to your hi-fi amp or receiver can be copied into your computer.
Both recording and playback are routed through the MobilePre, so I get to hear the playback on good speakers instead of lo-fi computer speakers. The MobilePre has a headphone port for zero-latency monitoring during recording, which is a nice thing to have. The Behringer mixer (Europower 1280S) isn't really intended to be a studio mixer; it's for powering live shows, which it does most ably, because it is an integrated mixer and 1200-watt amplifier. When I'm recording a live show, I hook up to it with a laptop and the MobilePre. I also have a Zoom H2 portable digital recorder, which I can use in place of the laptop plus MobilePre. The best-quality recordings at live shows come from plugging directly into the mixer board.
NOTE: The local old-time country band that I like to listen to and record has a rather eccentric sound system. They have a nice PA system, but instead of plugging everyone into the mixer board, only the singers' mics are connected to the mixer. All of the musicians have to bring their own instrument amplifiers. This makes for a cluttered stage, and recording is a nightmare—plugging a recorder into the mixer means the only instruments it hears are whatever the mics pick up. The Zoom H2 has a neat little adapter to mount it on a mic stand so I can position it anywhere, but it's not as good as a proper setup with everything routed through the sound board.
Let's take a closer look at the MobilePre because it is representative of a lot of USB recording interfaces. The MobilePre supplies 48v phantom power for condenser mics and has XLR and TRS jacks, a 1/8"stereo input, two 1/4"mono outputs, and a 1/8" zero-latency headphone port for monitoring. Both dynamic and condenser mics can plug into the XLR jacks, as long as they have XLR connectors. You could also use an XLR-to-TRS adapter to plug a dynamic mic into one of the 1/4" inputs. Its built-in ADC supports sampling rates from 8 to 48 kHz at 16 bits, and it draws its power from the USB bus of your computer, so it doesn't need its own power cord. It has physical gain control knobs and a volume control knob for headphones, so you don't need to dink around with software controls. (I'd rather twist a knob than fumble around some weirdo software interface any day.) You should be able to find one for under $150. At 16-bit/48 MHz maximum recording quality, it's becoming obsolete because comparable devices support 24-bit recording. Still, it's a great little device, and because it is USB 1.1 class-compliant, it runs on any computer without special drivers.
Figures 2-3 and 2-4 show the front and back of the MobilePre.
Figure 2-3: M-Audio MobilePre, front. From left to right: Channel 1 1/4" mono TRS jack, Ch. 1 and 2 gain controls, clip LEDs, headphone port, headphone volume knob, phantom power switch, phantom power LED, and power LED
Figure 2-4: M-Audio MobilePre, backside. From left to right: USB jack, stereo line out, 1/4" mono TRS right and left outputs, stereo mic in, Ch. 2 1/4" mono TRS input, Ch. 2 XLR mic jack, Ch. 1 XLR mic jack
Sorting Out Connectors
Where do the terms TRS and XLR come from? TRS is tip-ring-sleeve, which is the physical description of a TRS plug. Figure 2-5 is a labeled photo of a stereo and a mono TRS jack.
The origins of XLR are a little more complicated. Cannon Electric was the original manufacturer of the XLR connector, and some old-timers still call it a cannon plug. It started out as the “Cannon X" series of connectors. Then later versions added a latch, so there is the L, and then the contacts were encased in rubber, for the R. Figure 2-6 shows a pair of three-pin XLR plugs.
Figure 2-5: One stereo 1/400 TRS plug (left) and one mono (right).
Figure 2-6: Here is a three-pin male XLR plug and a three-pin female XLR plug.
Figure 2-7 shows a collection of plugs and adapters. You can find adapters to make anything fit anything. However, you must be careful—just because something fits doesn't mean it belongs there, so read your product manuals. Stereo TRS plugs have two black bands near the tip, and mono TRS plugs have one.
Figure 2-7: Two stereo RCA to 1/8" TRS plug, 1/4" mono TRS to two stereo RCA, 1/8" to 1/4" stereo TRS adapter, 1/4" to 1/8" mono TRS adapter
Figure 2-8 shows the three-pin male XLR connector on a Behringer dynamic mic.
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Figure 2-8: Behringer dynamic mic showing off its three-pin male XLR connector
Multichannel Recording, PCI, USB, FireWire
Multichannel recording is done in several different ways. One way is to use a simple two-track recording interface like the MobilePre. It supports up to six inputs at once and routes them into two channels. There are no mixer controls, so this requires some finicking during recording to get a decent balance. A better way to do multichannel recording with a twochannel interface like the Pre is to record two tracks at a time, giving each instrument or performer its own individual track, rather than trying to cram them all through the Pre at once. Then Audacity is your mixer, and you have individual control of each track. Another option for two-channel recording is a good-quality twochannel PCI sound card like the Emu 1616M PCI, which you can find used for under $200. It comes with a breakout box that supports all kinds of plugins, 24-bit/192 kHz recording, phantom power, and preamps.
My Behringer 1280S gets pressed into service when I have a larger group over for recording. Any analog mixer will work as long you have an ADC/ DAC to plug it into. My setup is a bit of a hack job since the Behringer is not really a studio mixer, but it works and sounds good, and it is an example of how a little ingenuity goes far in the wild world of audio. Like many mixers, the Behringer outputs to two-channel stereo, so I need to get the mix right during recording—I'll have only two channels to work with in Audacity. I could also record one or two tracks at a time with the Behringer and then knit them together in Audacity; there is no rule that says you have to plug in everything at one time. (Though corralling and organizing musicians can be a bit of a cat-herding experience, and sometimes you have to take what you can get.)
Audacity from version 1.3.8 supports recording as many tracks at once as your recording interface supports. Older versions max out at 16. This is where FireWire and the higher-end PCI sound cards shine, because they allow recording many tracks at once. The Focusrite Saffire Pro 40 is an example of a good value in a FireWire recording interface at about $500; this gives you 8 mic preamps, 20 total inputs and 20 outputs, 24/96 recording, blinky LEDs, and phantom power on every mic channel. The M-Audio Delta 1010 is a popular higher-end multichannel PCI sound card that connects to a rack-mount breakout box. It goes for about $600.
A cool new family of devices is USB and FireWire mixers. These give you everything in one device—preamps, phantom power, mixer board, ADC/ DAC, and direct plug-in to your computer. There are a lot of nice choices in the $300 to $1,000 range. Behringer's line of Xenyx USB mixers costs between $150 to $600. They use class-compliant USB 1.1, so they plug into any computer with no special drivers needed. The M-Audio NRV10 is a nice little FireWire mixer/preamp that costs about $700.
How to choose which of these to use? USB and FireWire are portable and easy to hook up. PCI Express is the fastest. One lane of PCI-E moves about 250MBps both ways at the same time. That's 250 megabytes, not megabits. Plain old PCI maxes out at 133MBps. Also, unlike PCI-E, PCI uses a shared bus, so more PCI devices means more bandwidth contention. Every PCI-E device has its own dedicated data pipeline, so PCI-E devices don't have to share bandwidth. USB 1.1 is rated at 12Mbps (megabits per second), and USB 2.0 is rated at about 480Mbps, but both figures are highly theoretical, and in real life you're likely to get half that. FireWire is rated at 400Mbps. However, FireWire gives you higher sustained throughput and better performance than USB, a difference that is discussed in more detail in the following section.
A common problem with internal sound cards is picking up noise and electrical interference from hard drives, power supplies, and fans inside your computer case. This usually isn't a problem with the better sound cards like Emu, M-Audio, and RME Hammerfall, but it tends to be more of an issue with consumer level and gamer sound cards and low-budget onboard sound. If you are getting some noise, the first thing to check is all your connections— make sure everything is hooked up correctly and anything that needs to be grounded is grounded. Sometimes moving a PCI card to a different slot makes a difference. Check your motherboard manual to see if you have shared PCI slots; you don't want to use a shared slot if the other slot is populated.
USB or FireWire?
If you like the convenience of a USB audio interface, you might also consider FireWire devices. How do you choose between FireWire or USB? USB devices usually cost less than FireWire, but the trade-off is you may get poorer performance because of the differences in the two protocols.
All FireWire interfaces have special controller chips, so they do not add any extra load to your computer's CPU. FireWire is a peer protocol, which means FireWire devices negotiate bus conflicts without using host CPU cycles. FireWire gives you two operating modes to choose from: asynchronous or isynchronous. Isynchronous mode means a device can reserve a certain portion of bandwidth all for itself that no other devices can use. So there are no collisions, which translates into high sustained throughput.
If your PC doesn't have a FireWire interface, it's easy to add one. PCI FireWire interfaces cost about $50, and many laptops include a FireWire port. When you're shopping for FireWire audio interfaces, be sure to check for hardware compatibility. As one example, the Presonus FP10 has known conflicts with certain video chipsets, and it has a limited set of FireWire interfaces that it is known to work well with.
USB operates only in asynchronous mode. A synchronous means that any device on the same bus can send data whenever it wants to, so sometimes there are collisions, which cause latency. USB is host-dependent and puts a load on the CPU, which can also cause latency. Latency is the enemy of quality audio.
You'll see a lot of USB audio devices that still use USB 1.1. USB 1.1 has two speeds: 1.5Mbps and 12Mbps. The latter is also called full-speed. It's unlikely that a USB recording interface will be geared down to 1.5Mbps. The number of channels you can record at once depends on the quality level you want to record at. CD quality, two channels at 16/44.1, has a bitrate of 1,411,200Mbps. Two channels at 24/96 equals a bitrate of 4,608,000Mbps, so it seems you could record four 24/96 channels at once. However, that 12Mbps maximum is theoretical, and your real-world throughput will be half that or less. Most likely you'll be limited to two-channel 24/96 recording at best. Four channels at 16/44.1 or 24/48 are possible if you are careful and have a good, fast multicore PC and have it tuned for audio production. (See “Bitrate, Bit Depth, and File Size" on page 29 to learn about different bitrates.)
USB 2.0 audio devices require careful shopping, because many of them are not USB class-compliant and instead supply their own special drivers. Even Windows users have to do their homework because vendors are slow to release drivers for new Windows releases. Mac support is decent overall, and Linux, Unix, and users on other platforms are at the back of the bus as usual. Some multitrack USB 2.0 devices are getting good reviews. For example, the M-Audio Fast Track Ultra 8R (eight in, eight out) gets high marks and works on Mac, Linux, and Windows.
Microphones
The microphones in Figure 2-9 are middle-of-the-road dynamic mics that cost less than $100 each. The microphone is very important—you won't get good recordings from low-quality microphones. There are two common types of microphones: condenser and dynamic. Condenser mics have a wider frequency response, are more sensitive, produce louder output, and have a faster transient response. Transient response is any abrupt change, such as a rim shot, a hard-strummed guitar, or a singer hitting some hard consonants (and probably spraying a bit of spit).
Figure 2-9: Audio-Technica stereo condenser mic, Behringer dynamic mic, and wind sock
Condenser mics require power. This is called phantom power when it is delivered through the microphone cable, because there isn't a separate power cable. They are more fragile than dynamic mics. Condenser mics live mostly in studios. They are also used onstage in combination with dynamic mics on drum kits; the condenser mics hang overhead to capture cymbals and transients, and dynamic mics are placed next to the drums. Figure 2-9 shows an Audio-Technica stereo condenser mic, a Behringer dynamic mic, and a wind sock. (Experienced singers know to avoid brightly colored wind socks because they look like clown noses.)
Condenser microphones that require phantom power typically use XLR connectors. Dynamic mics use both XLR connectors and TRS plugs. Dynamic mics do not require phantom power, so make sure that the phantom power is turned off before you plug one in to a phantom-powered XLR jack. It shouldn't damage the mic, but it will change how it sounds. It's common to see audio gear with both types of microphone connectors, and newer devices have combination jacks that accept both.
The little Audio-Technica Pro 24 stereo condenser mic in Figure 2-9 is a different kind of condenser mic. It is self-powered by a little mercury battery, it has a built-in cable, and it plugs into any 1/800 TRS stereo microphone jack, like on laptops, digital recorders, and camcorders.
There are two types of condenser mics: large diaphragm (LDM) and small diaphragm (SDM). Both record sounds evenly and accurately across their entire range, though LDMs have a reputation for creating a “warmer" sound. A large diaphragm mic has a better low-frequency range than a small diaphragm, but a small diaphragm mic of the same type has a better highfrequency response. Low tones are characterized as warmer, and high tones are characterized as cooler and brighter. You're going to hear all kinds of characterizations for sound quality: warm, cold, brittle, soft, hard, bright, dull, and on and on. Trust your own perceptions, and don't worry about what other people tell you you should like.
Figure 2-10: A modern AEA R84 ribbon mic
Dynamic mics have a narrower frequency response and are less accurate than condenser mics. They are rugged, are moisture-resistant, and don't need a power supply, so dynamic mics go on stage and in the field. Dynamic mics generally cover the human vocal range plus a little bit, so this makes them good for singers.
Another type of microphone is worth consideration, and that is the ribbon mic, which is a type of dynamic mic. The guts of ribbon mic are a metal ribbon suspended in a magnetic field. These are expensive but are prized for their clarity, spatial depth, and realism. They revolutionized the audio industries back in the 1930s; ribbon microphones set new standards for realism and accuracy that the condenser mics of the day could not match. Ribbon mics fell out of favor somewhat as condenser and dynamic mics improved. They were expensive, the metal ribbon was fragile, and their output was so low they needed more amplification than other types of microphones. Modern ribbon mics are more affordable and durable and produce louder output than their ancestors, so they're definitely worth trying (Figure 2-10).
Ribbon mics are natively bidirectional, which means they are sensitive to sounds from both the front and the rear of the mic in a figure-eight pattern. They are effective at blocking sound from the sides. The figureeight pattern is on the horizontal axis, so you can tip them sideways to get a different effect. A pair of matched ribbon mics placed next to each other at a 90-degree angle is called a Blumlein pair , or crossed figure eight. This creates a realistic stereo image. If you don't want to capture sounds from one side, for example the audience side, you'll have to block it somehow or find a ribbon mic with the capture pattern that you want.
Polar Patterns
Important considerations for microphones are polar patterns. Polar pattern describes a mic's area of sensitivity, as Figure 2-11 shows. These twodimensional diagrams don't show that polar patterns are three-dimensional, so keep in mind that they're not flat and horizontal; they encompass areas with height and depth.
Figure 2-11: Some common microphone polar patterns (Image Credit: Created by Wikipedia user Galak76, released under the GFDL.)
These are the common polar patterns:
Cardioid Picks up sound from the front and rejects sounds from the rear. Sub-cardioid is rather like omnidirectional, with a smaller range to the rear. Hyper-cardioid and super-cardioid have a narrower range in front, plus small lobes of rear sensitivity. This is common for stage mics and especially for vocalists. Different cardioid mics have different levels of sensitivity. Some have a wide pickup range, so they are good for a performer who moves around a lot, and some have a small area of sensitivity, so they are better at not picking up background noises.
Omnidirectional Picks up sound equally from all directions in a spherical area. Try arranging your band in a circle with an omnidirectional mic in the middle to get a spacious, natural sound.
Shotgun The most highly directional of all with a long, narrow front and smaller rear pickup range. These are commonly used with movie cameras of all kinds, from film to digital, professional and consumer, and are favorites of wildlife photographers.
Bidirectional Picks up sound equally well from front and back; does not pick up sounds from the side. (Not pictured in Figure 2-11.)
Half-omnidirectional, or hemispherical Picks up about a 180-degree hemispherical area. You can get some nice live recordings with one of these because it has a wide pickup area to the front and does not pick up noises from behind. (Not pictured in Figure 2-11.)
You might be thinking, why not just use shotgun or cardioid mics for everything so you zero in on just what you want to record? Do whatever you want; let your own ears and taste be your guide and select your mics to suit the occasion. Different brands and models of mics have different levels and types of sensitivity. For example, some are forgiving of a singer who moves around a lot, while others do a good capture only up close. Wireless headsets are wonderful for the energetic performer, and wireless mics mean no tripping over cables. Some mics emphasize bass frequencies more as you move closer, like radio DJs that boom forth with exaggerated bass. This is called the proximity effect.
The Cowboy Junkies Trinity Session album was recorded using a single ambisonic microphone that reportedly cost about $9,000. Ambisonics refers to surround-sound recording techniques and equipment that are supposed to produce a realistic, spatially natural sound. An ambisonic mic has multiple capsules to capture sound from different directions, anywhere from four to dozens. It's an interesting niche in audio production; look up ambisonic and SoundField mics if you are interested in learning more.
Which Microphones for Which Occasions?
There are different microphones for all occasions, such as voice, guitar, drum, and so on. Vocalists can be especially picky, because different mics color their voices differently. You'll find plenty of passionate opinions on this subject. Keep in mind that there are a multitude of factors that affect how good a recording sounds to you: how it's edited, the type of equipment you're listening to, your listening location (home, friend's house, performance hall, outside, vehicle), and your mood and expectations. We've grown up with decades of recorded audio of all types: acetate, vinyl, different types of tape, and now digital. So what sounds “right" is heavily flavored by what we're used to hearing. Some folks still hanker for the sound of tinny '60s AM radio or boomy jukeboxes or quadrophonic eight-tracks. Some believe that vinyl sounds “warmer" than digital and that tube amps sound warmer than solid-state.
I've always wanted to do some blind tests just to see whether the picky audiophiles in my life can really hear a difference. Number one on my blind testing wish list is tube amp versus solid-state, and cold tube amp versus one that has had a 24-hour warm-up, because some of the aforementioned picky audiophiles insist that tube amps need a long warm-up period or they sound “cold."
There are real differences between tube and solid-state. Tube amplifier systems drive a transformer, which in turn drives the speakers. The transformer suppresses a lot of transients like spikes, pops, and clicks, resulting in a cleaner sound. A cold preamp has more noise than a hot preamp. Tubes also have a singular noise source, whereas semiconductor devices have multiple noise sources, increasing the amount of noise you might hear. Still, on good-quality gear it's going to take some mighty fine hearing to detect the difference.
It is nearly impossible to define a “pure" experience, because even live performances are colored by their environments and equipment, ambience, and the way our brains process data. It always surprises me how much worse my favorite local band sounds on the recordings I make of its performances. During the shows, I'm having a great time and thinking they sound wonderful. Then later when I hear the playback, I hear all kinds of flaws: off tempo, out of key, lackluster, you name it. Maybe I'm too picky and too attuned to listening for mistakes on recordings; maybe during the live shows my brain is too busy having fun to notice flaws. Maybe I make lousy recordings.
The moral is sound quality depends on your own ears and experience— what sounds good and right to you is what matters. You can try for the most realistic fidelity or try for the best artistic and creative fidelity. It's all subjective.
Microphone Cables
There are many brands of microphone cables, and you can waste a lot of money on a snooty brand name. Don't spend a mint; there are many reasonably priced, good-quality choices. You may run into some confusion over balanced and unbalanced cables. In the context of connecting microphones, an unbalanced cable is a coaxial cable that terminates in a tip-sleeve (TS) connector. It has a single conductor wire surrounded by a combination shield and ground. These are effective at blocking external interference but are vulnerable to induced hum and noise and tend to be noisier than balanced cables. A balanced cable terminates in either a three-pin XLR connector or a TRS connector. It has two internal wires, one hot and one cold, surrounded by a shield that is not part of the signal path, so it supplies a cleaner signal. Balanced cables can run for much longer distances than unbalanced cables without picking up excessive noise.
Keep in mind that it is the signal that is balanced or unbalanced, and using a balanced cable will not make an unbalanced signal balanced. However, a TS cable will convert a balanced signal to unbalanced. You need to match your cables to your mics and your preamp, amp, mixer, or whatever you might be plugging into. Condenser mics that depend on phantom power mostly likely use three-pin XLR balanced cables, and dynamic mics use balanced cables with both XLR and TRS connectors. A balanced signal doesn't care what carries it, so you can use XLR-to-TRS adapters as needed, provided that whatever you're plugging into sends the correct signal.
These days this shouldn't be something that you have to spend a lot of time figuring out, since most contemporary audio gear supports balanced mic connections.
Microphone cables are either stiff or flexible, depending on where they're going to be used. Flexible cables are for live performances, and stiff cables usually reside in studios where they are not moved very often.
Don't cross electric lines with any of your audio cables if you can help it, because you may pick up interference. If you have to, cross them at right angles to reduce the overlap.
Smart Miking
Placing your microphones for best results is an art in itself, and the only way to get good at it is to practice a lot. You want to be as close as possible but not so close that you pick up electronic interference or unwanted sounds such as lip smacks and spit from vocalists. Pop filters are helpful for vocalists, and windscreens are essential for outdoor recording.
The “3-to-1 rule" is a simple guide for microphone placement for live performances or in the studio when you have several mics and performers set up at the same time in the same room. When microphones are placed too close together, you may get squeals, dips and peaks, or other forms of unpleasant interference. The 3-to-1 rule means the distance between adjacent mics should be approximately three times the distance between the mic and the sound source. If there are multiple amps present, as with my fave local band where every performer lugs their own amp onstage, these will cause problems too. Sometimes simply turning an amp to face in a different direction will cure feedback problems.
Microphone stands are essential—don't depend on hand-holding. Goosenecks take up less space and are fast to adjust, but over time they wear out. Boom stands last forever but take up more space. Some folks prefer tripod feet, which I always trip over, so I prefer weighted bases. Shock mounts and cages are great for isolating your mics from vibrations and don't cost very much.
Microphone Preamp
Microphone preamps are the second most important devices in your audiochain, after ADC/DACs. As I've already talked about in this chapter, I have an M-Audio MobilePre and a Focusrite Saffire Pro 26. With these I don't need an internal computer sound card or separate preamp, because they have their own built-in microphone preamps. However, even if you prefer to use an internal sound card or have good external recording interfaces, you may still want to use a separate microphone preamp. Let's talk about why the preamp is so important.
A preamp—short for preamplifier—amplifies a low-level signal to line level. The output from a microphone, a turntable, and many instrument pickups is lower than line level. Line level is a standard analog audio signal voltage that is designed for connecting different audio components. What is this voltage? Well, that's a good question because even though it is billed as a standard voltage, it varies depending on the manufacturer. Most are around 1 to 2 volts. A preamp has a significant effect on audio quality: A low-quality preamp will introduce noise and distortion. A good preamp amplifies the signal cleanly, without introducing defects or color.
NOTE: Audio terminology gets bent in all kinds of ways—many of the preamps you see for home hi-fi systems are not like microphone preamps because they don't do any amplifi- cation but are just switching units where you plug everything in.
Preamps range from bare-bones models that supply only gain (ampli- fication) and phantom power to gaudy delights larded up with all kinds of special effects, dials, and blinky lights. A lot of audio devices come with gobs of special effects because it costs practically nothing to add them, and they make you feel like you're getting something special. If you like lots of special effects, this is a nice bonus; just don't let it distract you from a device's real quality. At the least it is nice to have some physical knobs. Debates over which preamps are best almost take on a religious quality. Professionals might spend thousands of dollars on a single preamp. You're welcome to do this, but in my opinion you're better off starting out with inexpensive gear and investing in perfecting your recording techniques. Then when you're ready to move up to better gear, you'll appreciate the difference and know how to get the most out of it.
Speakers and Headphones
Having both speakers and headphones in your audio chain lets you hear your recordings in different ways. Studio monitor speakers are supposedly dead-flat and accurate and don't add any color of their own. They also tend to be expensive. My own studio speakers are a set of nice JBL three-way speakers. They're not real studio monitors, just nice speakers that I like. Headphones are essential—you need these for monitoring your recordings. Audio interfaces that include built-in zero-latency headphone ports are perfect for monitoring. I seem to collect headphones: I have a nice Plantronics USB headset, which is great for recording podcasts; a set of Sennheiser headphones with an ordinary ¼” TRS plug; and wireless Audio-Technica headphones. My studio speakers are powered by a nice old Pioneer SA 7500 stereo amplifier. I've had it repaired twice, and I'm going to keep it going as long as I can. It's rated at 45 watts per channel, which doesn't sound like much, but it powers those watts with some serious amperage. Amps are the real measure of power in an amplifier; that is what makes the difference between a wimpy amp and a good strong clean amp. Wattage doesn't mean all that much—that's just the number salespeople like to focus on.
None of this is super-duper hi-fi, at least not according to fussy audiophile standards, but they're all good components, and they please me.
Your Computer Must Have Muscle and Vast Drawers
Your computer should be a good modern machine with a high-powered CPU and a lot of RAM. My studio PC has an AMD Phenom triple-core CPU with 4GB RAM. Multicore CPUs make a big difference. A single-core CPU should perform fine for two-track recording and simpler recordings like podcasts and interviews. For example, I have an old ThinkPad with an 800 MHz CPU and 256MB RAM running Linux that performs nicely as a field recorder for interviews. For more than two tracks, multicore is the way to go. Don't worry about AMD versus Intel; they're both fine, so use whichever you like best.
You need as much storage as you can afford. CD-quality audio (44.1 kHz, 16-bit WAV) uses around 5MB per track per minute. Don't forget to add up all the tracks you are using and all the retakes. You can buy terabyte hard drives, and by the time you read this, they'll probably be even larger. Another option is to combine the capacity of several hard drives in a RAID (redundant array of inexpensive disks) array. The two RAID levels that are useful for audio production are RAID 0 and RAID 10. RAID 0, also called striping, makes two hard disks look like one, so two 500GB drives appear as a single terabyte drive. RAID 0 is very fast but has the same weakness as a single drive—if one drive in the array fails, you'll probably lose all of your data.
RAID 10 (using a good-quality hardware controller) is mirroring plus striping, so you get speed and redundancy. Use a good-quality hardware controller; you don't want some cheapie that dumps more load on your CPU but instead one that handles the load itself. It's more expensive of disks than the popular RAID 5, but it's more reliable and a lot faster—you get faster reads and writes and much faster recovery from a failed drive. I wouldn't use RAID 5 or 6 arrays for audio recording; in fact, I don't use them at all anymore because they're too fragile, they're too slow for writes, and they propagate parity errors too readily.
I wouldn't worry about building some super-duper RAID array for recording and editing with Audacity, unless you find yourself burning through terabyte hard drives all the time. I use a single large hard drive on my studio PC and am ruthless with housekeeping and getting rid of unneeded files. I use a nice little four-disk Linux-powered RAID 10 server for backups.
Operating Systems
In this book I will be covering both Linux and Windows. Each one has its strengths and pitfalls. If you're a Windows user, XP is still the most reliable version even though Vista and Windows 7 have been released. You'll get the best hardware and software support and the best performance. Vista presents special problems because of its own high hardware requirements— it may bog down your system to the point that you can't comfortably use it for audio recording, and driver support for many audio devices is immature. Audio hardware manufacturers seem a little more interested in Windows 7, but it is still a hog compared to XP. If you want to upgrade from XP, don't bother with Vista; go straight to Windows 7. If your audio hardware and software work well on XP, then keep them as long as you can.
Linux users have the usual hassles with hardware manufacturers pretending they don't exist no matter how many products they buy, hype, and give free support for. Appendix A will tell you what works well in Linux, and you'll also find links to sites with current information on audio hardware support in Linux. If it's any consolation, a lot of audio hardware vendors don't release very good Windows drivers either. Why? Who knows; it is a mystery that I waste too much time wondering about. Don't they want happy customers?
Latency is the enemy of quality audio, so please refer to Chapters 13 and 14 for tips on tweaking your operating system for best audio performance.
Here are system requirements per the Audacity documentation. Assume the same for Windows 7 as for Vista:
Windows 98, ME 128MB/500 MHz recommended, 64MB/300 MHz minimum
Windows 2000, XP 512MB/1 GHz recommended, 128MB/300 MHz minimum
Windows Vista Home Basic 2GB/1 GHz recommended, 512MB/ 1 GHz minimum
Windows Vista Home Premium/Business/Ultimate 4GB/2 GHz recommended, 1GB/1 GHz minimum
Linux “Audacity will run best with at least 64MB RAM and a 300 MHz processor," says the Audacity documentation for Linux users. I recommend a minimum 800 MHz CPU and 256MB RAM for podcasts, interviews, and two-track music recording and the most powerful threeor four-core CPU you can afford for multitrack recording and editing.
Portable Recording
There are several good methods for field recording. My two favorites are to fix up a netbook as a portable recording studio or to use a portable digital recorder. Netbooks are so cool; I've been wishing for netbooks ever since I discovered computers. Ordinary laptops work fine too, and you get more powerful CPUs. You have all the same options as you do with a desktop computer—your choice of preamps, mixers, and other audio interfaces, microphones, software—and you can do all of your editing on the spot and even burn CDs. You also have a nice screen and keyboard, instead of the tiny screens and buttons found on portable digital recorders.
Pocket digital recorders work wonderfully well and are fun. These range from tiny keychain fobs that are the audio equivalent of sticky notes to little recorders for good-quality voice dictation to high-quality multichannel recorders. Let's see what goes into a high-quality unit.
Figure 2-12: The Zoom H2 with an RCA-to-1/800 stereo plug adapter for connecting to a mixer or any other two-channel stereo RCA recording or line output
There are a large number of them that are priced reasonably, and you can slip one in your pocket and carry it anywhere. Carry extra batteries and some extra storage cards, and you're ready for anything. My personal favorite is the Zoom Handy H2 (Figure 2-12). It runs on two AA batteries and also has an AC adapter. It has four built-in good-quality microphones, so you can record either in two-channel stereo or in four-channel surround. It has no speakers, but it comes with earbuds, and it can also be used as a USB audio interface on a computer. Its 1/8” line input can be connected directly to the sound board at concerts, and it also accepts an external microphone. It uses SD cards for storage and supports both WAV and MP3 file formats. It costs about $150.
Some other popular and excellent portable digital recorders are the Olympus LS10, Marantz PMD 620, Marantz PMD 660, Sony PCM-D50, Yamaha Pocketrak 2G, and Zoom H4. All are under $600, and all have built-in mics. Ideally you'll be able to get your hands on them and give them good test drives before purchase because they share a common weakness—tiny LCD control panels with complicated menus. You'll also want to test noise levels, because some of them are nice and quiet when you use the internal mics but are scratchety with external mics. Most of them accept external mics—some have only 1/8” mini-jacks, and some accept full-sized XLR or TRS plugs. The ones that have XLR jacks don't always supply phantom power for condenser mics. A nice option is to use a battery-powered condenser mic, and then you don't have to worry about phantom power.
NOTE: Devices that supply phantom power usually advertise “48v phantom power." But few mics actually use 48 volts. They usually use much less—as little as 8 to 10 volts.
Some other things to look at are battery life, type, and size of storage cards. Does it have any built-in storage, and what audio file formats does it support? Does it come with useful accessories such as AC adapters, windscreen, earbuds, and stands?
An interesting variation is the M-Audio Micro Track II. This has no built-in mics but is a miniature two-channel recording studio meant to be used with high-quality external mics. It supports both dynamic and condenser mics and supplies a full 48v phantom power for condenser mics. I prefer to use a USB card reader for transferring files from a portable recorder to my computer. Usually it's faster, and it doesn't run down recorder batteries.
The Secret of Recording Your Own Great Audio
The “secret" behind making good-quality audio recordings isn't much of a secret: The most important factor is blocking out unwanted noises. Our brains are wonderful at ignoring sounds we don't want to pay attention to, but microphones give equal attention to all noises. Blocking unwanted noise is harder than it sounds because our modern world is very noisy: vehicle traf- fic, airplanes, appliances, televisions and stereos, fluorescent lights, $2,000 powered subwoofers roaming the streets at 120 decibels in $500 cars, construction, and so forth. High-frequency noises are easier to block than lowfrequency sounds, as we all know from our futile attempts to escape those four-wheeled powered subwoofers, which pound their way through all barriers.
Computers add their own sounds—it's common to pick up hard drive and fan noise. So before you stock up on fancy recording equipment, job one is preparing your recording studio:
- Use a quiet room with sound-absorbing walls or wall coverings. Old carpet and blankets work as well as spendy acoustic foam.
- Place a good directional microphone close to whatever you are recording and aim it carefully.
- Shield your mic from your PC.
- Adjust your sound levels carefully, neither too low nor too high.
- Mount your microphones in shock cages.
But, you may ask, why go to all that trouble? Why not just fix it later? It's all just software anyway. My dear reader, if it were as easy as silly TV shows and movies portray it, there would be no need for soundproofed music recording studios, and no one would ever holler, “Quiet on the set!" You can mitigate problems somewhat in Audacity, but you get better results making as good a recording as possible and saving the fix-its for problems you can't avoid. It's nothing like crime shows where ace audio techs can clean up any recording, no matter how mangled, to perfect high fidelity. That's beyond fiction and well into fantasy.
Your PC should be dedicated to the job and not used for anything else, neither gaming nor web surfing nor emailing nor anything, because you want all of your computer's power dedicated to recording. If you don't, you risk generating skips and stutters. Turn off screensavers, all power management, and any antivirus or antimalware software. (Windows users, do I need to say, don't be connected to the Internet after doing this?) Turn off all unnecessary services, scheduled jobs, and everything that is not essential.
Your microphone will pick up noise, vibrations, and interference from a surprising number of sources. If you still have an old cathode ray tube (CRT) monitor, replace it with a modern flat thin-film transistor liquid crystal diode (TFT-LCD) monitor, because CRTs emit radiation and noise. Sometimes they even resonate to certain sounds and create echoes.
You can make an effective sound barrier between mic and computer for cheap by attaching a piece of carpet to a piece of plywood or particle board. Give it feet so it stands on its own, and you have the equivalent of an expensive piece of a high-tech sound barrier. Both laptop and desktop machines should sit on nonresonating surfaces. In a pinch, you can set your laptop on a coat or a pillow, being careful to not block its cooling vents.
Although many how-tos advise making your studio as acoustically “dead" as possible, without any echoes or resonance, feel free to experiment. You might like how some things sound in a space with some hard surfaces. Psychoacoustics come into play in professional recording studios; they don't make perfect anechoic chambers because those are so flat that they sound unpleasant. There is no sound reflection, nothing that gives depth to sound. So, professional studios reduce the amount of random noise while preserving some depth to the sound.
Visit Appendix A
Now that you have some ideas on what you need, please visit Appendix A for a sampling of good audio gear in all price ranges. This should help you navigate the huge and splendid world of audio hardware.
Layla and Firecracker, the official studio dogs, wish you well (Figure 2-13).
Figure 2-13: Layla and Firecracker waiting for their cues
