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Behind the Music: Digital Audio Components
Go beyond a PC's burps and beeps to improve your listening experience with the vast array of digital audio components on today's market. It's like music to your ears.
William Van Winkle
Until the late 1980s, the only sound you could expect a PC to make was beep. Maybe if you were playing a game, the tiny two-inch speaker mounted inside the case would make rudimentary noises that sounded less like music or sound effects and more like digital flatulence. Ultimately it all boiled down to variations on the theme of beep.
In 1989, a little company called Creative Labs introduced the Game Blaster, which soon gave way to the Sound Blaster, which soon gave way to an entire sub-industry in PC audio. Today, many PC-based sound systems outperform conventional home stereos, and hardly a single PC is manufactured without high-fidelity circuitry that would have amazed any PC owner a decade ago.
PC-based audio isn't only about music reproduction, although playing CDs and downloaded music is certainly a main reason why the technology evolved so quickly. Just consider all the audio integrated into Web-based applications, particularly Macromedia Flash movies and voice applications (aside from recording), such as voice chat and speech recognition. We now play DVDs on our computers, portables, and MIDI devices that transform PCs into full-blown composition studios. As most gamers know, nothing beats an action game accompanied with thundering bass and crystalline surround sound.
A PC's audio components bring the sounds alive, with other equipment now pushing those boundaries beyond the PC's walls. Inside many chassis is one of today's hottest sound products, the descendant of the Game Blaster, Creative Labs' Sound Blaster Audigy ($199; www.creative.com), which sets the standard.
Anatomy of an Audigy
You could look at a Ford and look at a Chevy and decide most contemporary automobiles have a lot more in common with each other than they do differences. Similarly, the shared underlying mechanics and basic elements of modern sound cards are largely the same, but they may vary in fine details. We'll take a close look at those specific details.
Creative Labs' Audigy Platinum products include the PCI card and either a bay-mounted front plate or an external drive that replicates numerous ports for more convenient access. From the outside, cable jacks are the only evidence of a sound card. On the card itself, the Audigy offers five mini-jacks plus an IEEE 1394 port. Each jack is gold plated, a common feature in high-end audio gear because of gold's superior conductivity and resistance to oxidization, which could eventually lead to a bad connection.
The area surrounding the jacks is not colored, which is something of an abnormality in current sound adapters. The PC99 guide specification (Microsoft/Intel-sponsored Design Guides) recommends that the four primary audio jacks each have their own set color code to help users plug the right wire into the correct jack. The PC99 colors are: pink for microphone (mono), lime green for stereo-out, light blue for stereo line-in, and the rear channel stereo-out/headphone jack had no set color. Unfortunately, the design guide ended in 2001, so whether the old coloring convention endures remains to be seen. Apparently, Creative has abandoned it already.
The Audigy Drive
The Audigy drive is a front plate full of the ports of the Audigy card. It is installed in an open drive bay on the front of a computer, and a ribbon cable attaches to it and to the Audigy sound card. It is analogous to a notebook docking station. The ports found on the card's backplane are moved to the front of the PC for easier access.
In addition, there are several additional ports, including coaxial S/PDIF-in and -out and optical S/PDIF-in and -out. Interestingly, these two connector types are functionally identical. Both carry digital S/PDIF data. Only the cabling type is different. The advantage of supporting optical cabling is that this is a popular format in high-end home-theater systems. Present on the Audigy drive are infrared (for use with the included remote control) and MIDI-in and -out. For those who frequently handle audio peripherals, the Audigy drive offers tremendous convenience.
The centerpiece on the Audigy's circuit board is the Audigy chipset, now physically large enough to rival most motherboard chipsets. Like the graphics processor on a 3D graphics card, sound adapter chipsets are designed to handle audio processing tasks so that it's not necessary for the main system CPU to perform this action. These functions include everything from computing each of the Audigy's 64 simultaneous voice channels to Dolby Digital decoding to tracking an object through 3D audio space.
The Audigy also includes SoundFonts and Environmental Audio Extensions (EAX). Creative's EAX technology uses reverb and other acoustic factors to simulate certain types of surroundings. Merely by switching the environment setting, a speaker might sound as if in a concert hall or stuffed in a closet. Numerous other vendors have adopted EAX, and the technology is now a main staple in games and other applications.
Other Sound Cards
Despite its numerous models and incredible popularity, the Audigy is not the only sound card available in the PC market. An increasing number of sound cards are not even cards but rather chips and interface ports mounted directly onto motherboards. If you're familiar with the many drawbacks of motherboard-based video, don't jump to the conclusion that integrated audio suffers from similar detriments; quite the opposite is often true.
Integrated audio began with the release of Intel's i810 chipset aimed at Celeron-based budget systems. Integrating the audio into the system chipset was an easy way to eliminate the need for an add-on sound card and to shave $20 or more from the final PC price. The i810's audio functionality adhered to the Audio Codec 97 (AC97) specification, which handled both stereo audio processing and 56-Kbps software-based modem tasks. Original AC97 offered only two-channel stereo, perhaps based on the assumption that those corporations that buy low-cost motherboards don't want their employees listening to surround sound. More recently, updates to the AC97 spec have included support for S/PDIF, rear-channel speakers, and 3D stereo enhancement.
Intel is not the only integrated audio player in town. Creative has a long history of licensing its low-end chips, such as the Vibra 16, for third-party use, and companies like ESS Technologies and Cirrus Logic have very competitive chips aimed at the budget-end market. Cirrus's CS4630 SoundFusion DSP, for example, features Sensaura and EAX (both 3D positional and reverb algorithms), 10-band graphic equalization, echo cancellation for NetMeeting, and unlimited voice wavetable synthesis.
As a technical aside, know that wavetable is a must if you're into realistic audio. Audio cards of the early 1990s were almost entirely based on FM synthesis, wherein analog sound waves are synthesized and combined to produce a rough approximation of a given instrument or sound. With FM, a grand piano will sound similar to a piano. Wavetable synthesis modulates actual digitized recording samples of a grand piano so that it sounds exactly like a grand piano. Low-end audio chips may not include wavetable support, since wavetable voices, or sampled sounds, must either be stored in permanent memory on the controller (more expensive) or downloaded and installed by the user (increased complexity).
Despite its strong position on many store shelves, Creative Labs is not exclusive in offering add-on sound cards, although the company has either crushed or absorbed most of its competitors. Ensonique, which originally developed wavetable technology, is now a Creative property. Media Vision, Creative's chief rival in the early- to mid-1990s, falsified its SEC filings and went under. Several Media Vision engineers founded Aureal and created A3D, a positional audio technology arguably better than EAX. The argument ended in 2000 when Creative purchased the defunct Aureal and buried A3D. Gravis dabbled in sound cards, as did Diamond Multimedia, and both quickly fled before Creative's onslaught.
A few rival sound card manufacturers remain, chief among them being Voyetra Turtle Beach. Turtle Beach's flagship adapter is the Santa Cruz, a card with a look that reflects its $79.95 list price, but which packs a heavy-duty punch. Along its backplane edge are the four conventional audio jacks (mic-in, line-in, front-out, rear-out) and a MIDI/game port. The key addition is a fifth, one-eighth-inch port called the VersaJack, an inventive feature that can be either an output for fifth and sixth channels, stereo line-in for third and fourth channels, or digital-stereo-out. The digital signal processor (DSP) chip on the Santa Cruz can be optimized for either accelerating 3D positioning functions or MP3 decoding, depending upon the current task. Turtle's Windows software lets you fine-tune an amazing number of card functions to get excellent sound quality.
Hercules, now owned by Guillemot, offers its Gamesurround Fortissimo II ($49.99). Based on Cirrus Logic's SoundFusion CS4624 chip, this simple looking card supports all the main positional audio protocols, optical-in and -out (a rarity at this low price), and an odd DIN connector that cables out to a four-way pigtail supplying line-in, mic-in, front-out, and rear-out jacks. The Fortissimo II supports 4.1 audio through analog and includes a bundle of useful software apps and is a great 3D audio solution for cost-conscious buyers.
For those on a rock-bottom budget, consider Philips's Rhythmic Edge ($29.99). The Rhythmic Edge is based on the ThunderBird Q3D chipset, jointly developed between Philips and QSound Labs. The card supports two-channel output only, but thanks to QSound, the simulated 3D effects created in software make a simple stereo speaker set come alive. The ThunderBird is a terrific accelerator chip, and anyone who regularly listens to PC audio with headphones will find this card a pleasant and affordable surprise.
Connected Sound
Not all PC audio comes from inside the PC. There may be times when you want sound processed outside of the computer, especially when the CPU is busy running other tasks in the background. Audiophiles will appreciate external audio solutions because they are removed from the noise-causing RF interference produced by PC components, such as the power supply. Alternatively, you may have to move between several machines and take the audio subsystem with you.
Laptops are notorious for having underpowered audio. An external sound solution can make all the difference between humdrum stereo and earthshaking surround sound.
The first and best example of this genre is Yamaha's Convergence of Audio Video and Information Technology (CAVIT). The first external Yamaha soundboard/amplifier, the RP-U100 arrived in 1999, well before Creative's better-known Extigy. The current CAVIT product is the RP-U200. Essentially, the CAVIT is an external USB sound card. The PC or Mac offloads all the audio processing onto the CAVIT unit. The unit features an integrated amplifier, anticipating the use of the passive (non-powered) speakers found in most home-theater systems. The RP-U200 integrates an FM-radio tuner and is intended primarily as a bridge product between the computer and the home-entertainment system.
The CAVIT includes Yamaha's built-in DSP effects chipsets (for presets like Jazz, Hall, Music, Games, etc.), 5.1 Dolby Digital and DTS hardware decoders (six-channel DTS is less common than Dolby Digital, but some argue that it offers superior sound quality), and Yamaha's CinemaDSP. Analog and digital auxiliary inputs let you plug in almost any audio device, from an MP3 player to your an old 8-track deck. The CAVIT delivers 14 watts to each of the five speaker channels, features a dedicated subwoofer output, optical out, and even a nine-band graphic equalizer. We were a bit leery about passing this much functionality across a USB 1.1 data pipe, but the Yamaha representative we spoke with stated only one case of USB-caused stuttering in the product line's entire history. CAVIT output and recording quality is exceptional, but the RP-U200's $449 price tag restricts its use to audio hobbyists.
Whereas the 12-pound CAVIT is designed as a stationary home device, Creative Labs' sub-four-pound Extigy ($149.99) is aimed more toward mobile users. The thin USB-based box is an attractive external version of the Audigy. All Audigy ports are replicated, save the SB1394. (1394's 400-Mbps speed specification couldn't possibly function across the Extigy's 12-Mbps USB 1.1 connection.) Both optical and MIDI-in and -out ports are present, along with a separate mini-jack dedicated to the center/subwoofer channel. For users with a single desktop computer, the Extigy is an odd purchase. For an easy upgrade to 5.1 audio, particularly with notebooks, the Extigy is cost-effective and powerful.
One interesting internal/external combination product is the Hercules Game Theater XP ($129.99). This package combines an internal Hercules PCI card based on the Crystal CS4630 chip with an external breakout box. The card's backplane features only a line-in mini-jack and a DB-44 port (44-pin connector) that connects to the breakout box. The box features a wide array of ports on its front and back, such as six gold-plated RCA connectors, four USB 1.1 ports, S/PDIF-in and -out, and MIDI-in and -out. All major environmental audio specs are supported, including Dolby Digital and DTS. Because of the PCI card, this obviously isn't a notebook product, and since the DSP is located on the card, the system's processor continues handling a heavier load than what a CAVIT or Extigy would inflict. The GTXP's key points are lower sonic interference, thanks to being distanced from noisy internal components, and easier access to a plethora of ports.
One should note that not all sound products are devoted to supplying every audio jack or processing cutting-edge 3D effects. You may simply want your existing audio to sound better. SRS Labs was formed in the mid-1990s following the acquisition of numerous audio and speaker technologies from Hughes Aircraft Company. In particular, SRS's WOW technology, present in Windows Media Player version 7 and above, specializes in simulating extended bass (TruBass) and a broader audio image from two-channel speakers, so the sound feels deeper and bigger.
SRS packaged its WOW technology into a fist-sized, translucent box called the WOW Thing ($19.95). The WOW Thing does not require a computer. Simply place it between any player device and a pair of speakers or headphones, and the resulting sound can be adjusted with varying amounts of TruBass and WOW. The device works equally well on a $40 Walkman as on a $4,000 workstation. Aside from being a great inexpensive gift, the WOW Thing does perk up the audio for those lacking the space, money, or enthusiasm for more complex external products.
Outside the Box
So far in this article we've fed into the commonly held concept that digital audio components pertain almost exclusively to the PC. This is a 1990s way of thinking that began when CD-ROMs played music CDs, and it has persisted with mega-components like the Audigy. Just as sound travels freely through the air, digital audio wants to travel away from the computer. The most obvious example is portable MP3 players, first popularized by the Diamond Rio.
Today, many MP3 players support alternative space-efficient codecs like Windows Media Audio (WMA) to fit two or three times as much music on the same amount of flash memory. A computer is often necessary to transfer files into the player, after which the user is free to roam with his tunes or audiobooks.
Newer hard drive-based jukebox players, like the 20GB Archos Jukebox Recorder ($319.95), can rip files directly from a source without the assistance of a PC, and store hundreds of hours of audio in a pocket-sized device that weighs less than a pound. With this amount of storage, a user might go for months without ever connecting to a PC for fresh audio files.
Another device type that could possibly thrive is the networked stereo component. One of the first examples of this was the amplifier-sized ReQuest ARQ1, which featured a hard disk and CD-ROM mounted in an Ethernet-enabled box. Users could rip audio files from CD, external analog sources, or remote network locations, store them on the local drive and then output them over the home-stereo system while viewing the visualization patterns on a TV.
A year ago, a 30GB ARQ1 retailed for $1,195. Today, the 40GB ARQ2-PRO costs $2,950 with nary a hardware change save for the increased disk capacity. The difference is that ReQuest ARQ2 units are now compatible with Crestron and other touch-sensitive control units with components marketed toward the affluent home-automation crowd.
Heirs to the ARQ1 include Compaq's iPAQ Music Center ($999). This device provides a 20GB hard drive, USB ports, and networks by HomePNA (telephone line) rather than Ethernet. Last summer, the Music Center retailed for only $799, likely due to lack of consumer adoption for such devices, which is now forcing vendors to try and recoup their costs. Entering track information on a remote control can be unwieldy, and while online track lookup does help, setup and regular use of this device class is definitely not for impatient novices.
Turtle Beach looked at this component market and took a different, possibly more successful track. Turtle Beach's AudioTron connects by either HomePNA or Ethernet and uses files located on the network's PCs. The AudioTron lacks a hard disk or CD-ROM drive, which keeps costs significantly lower. It offers S/PDIF and analog-out jacks for conveying files from the network to home-theater equipment. Software enables users to tune into Internet radio broadcasts. The bundled AudioStation application will be familiar to anyone versed in MUSICMATCH or similar jukebox titles.
People want music and other digital audio files distributed throughout their lives, and the AudioTron seems the best answer thus far for enabling this in the home. It is likely that music server appliances or even multimedia gateways will store not only hundreds of gigabytes of music and movie files, but will start to fetch such material via the home's broadband connection. Consumers are waiting for prices to drop and for both features and interfaces to improve.
The digital audio industry is full of innovation and attempts to add more value into our everyday listening experiences. Some of these attempts succeed, while others do not. Even in this early stage, the amount of power, quality, and versatility found in today's PC-based audio components is staggering. Whether you're an orchestral composer or a new gamer, there are many ways to enhance digital listening. If you're listening to bland stereo or dead silence on your computer, it's time to ask yourself why.
Archos Technology, Inc.
(949) 609-1400
www.archos.com
Cirrus Logic, Inc.
(800) 888-5016
www.cirruslogic.com
Compaq Computer Corp.
(800) AT-COMPAQ
www.compaq.com
Creative Labs, Inc.
(800) 998-5227
www.creative.com
ESS Technology
(510) 492-1088
www.esstech.com
Hercules
(888) 293-2648
www.hercules.com
Philips
(800) 531-0039
www.pcsound.philips.com
QSound Labs
(403) 291-2492
www.qsound.com
ReQuest, Inc.
(518) 237-5423
www.request.com
SRS Labs, Inc.
(800) 2-HEAR-3D
www.wowthing.com
Voyetra Turtle Beach, Inc.
(800) 233-9377
www.turtle-beach.com
Yamaha Electronics Corp., USA
(888) 435-7932
www.yamaha.com
Audigy Jacks (Top to Bottom)
Analog/digital-out: Usually this jack is used for output to digital speaker systems and can function as an analog-out port for driving a surround-sound center channel or subwoofer.
Line-in: This is where external audio devices are plugged into your PC's interface. For example, if you wanted to convert your vinyl albums into MP3 files, you would plug your LP player's or home-stereo amplifier's line-out wires into a two-in, one-out "Y" adapter, which would then plug into this stereo mini-jack.
Microphone: This receptacle is primarily for microphones, although other mono sources, such as voice recorders, might be used.
Line-out: This stereo output jack connects a standard pair of powered speakers. Alternatively, some users may connect this port to an amplifier in order to play PC-based audio over a conventional home stereo.
Rear speakers-out: For users with surround sound, this port connects the rear pair of analog speakers.
SB1394: Apple identifies the IEEE 1394 specification as FireWire, Sony calls it i.LINK, and Creative Labs refers to their incarnation of the port as SB1394. The IEEE 1394 spec is set in stone, and there is no difference between an SB1394 port and any other 1394 port, so in addition to acting as an interface for digital camcorders, any other 1394-compliant device will work with this jack.
The five audio jacks are now fairly standard on most mainstream- to performance-level audio cards. The SB1394 port is somewhat unique for a sound card and will most likely disappear in future audio adapters because the interface adds cost to the card. Ports for 1394 will most likely become an integrated motherboard feature, similar to Ethernet and modem jacks.
On the Audigy's circuit board, there are seven other jacks worth noting:
Telephone answering device (TAD)/modem audio: Some modems have a jack that links to the sound adapter, enabling calls to be automatically answered and recorded--this is where that wire is connected.
CD audio-in: CD-ROM drives feature an analog audio-out connector that feeds into a thin, often red-and-white wire that plugs into this connector. Without this connection, you cannot hear CD music on the PC unless you use the headphone jack on the front of the CD-ROM drive, or configure your system to process digital-audio output from the CR-ROM drive.
Auxiliary-in: Similar to an auxiliary port on a stereo amplifier, this jack is intended for additional peripherals, such as a TV tuner card or a second CD-ROM or DVD-ROM drive.
Internal SB1394: This connects the sound card to the Audigy drive (explained below).
CD S/PDIF: Pronounced "spee-diff" and commonly called S/PDIF or a Dolby Digital interface, the Sony/Philips Digital Interface connects with devices capable of handling digital audio not yet converted to analog. Many DVD-ROM and CD-ROM drives feature S/PDIF outputs that plug into this port.
Digital audio connections like S/PDIF are important, because with a digital signal there is no chance of nearby electromagnetic interference distorting the audio signal, a common problem with analog connections. Like any other audio connection, there are S/PDIF-in and -out ports. The S/PDIF jack on a CD-ROM drive is an out port; the CD S/PDIF jack on the Audigy is an in port.
Joystick/MIDI: Most sound cards feature a D-shaped 15-pin game port alongside their external jacks. The Audigy moved this port to accommodate the SB1394 jack and instead mounted the port to the Audigy circuit board itself, requiring users to plug in a ribbon cable leading to an external jack on its own dedicated backplane slot. This was a smart move on Creative's part. Gamers using USB-based joysticks don't need a MIDI port. To cater to music enthusiasts, Creative routes MIDI-in and MIDI-out in the form of the standard MIDI DIN connectors to the Audigy front panel. Musical Instrument Digital Interface (commonly referred to as MIDI) is the music format used to link instruments to computers, so it makes perfect sense that users would want to plug into the more convenient front panel or external Audigy drive, rather than a rear-mounted plug.
S/PDIF extension (digital I/O): This port connects via ribbon cable to the Audigy drive and handles the digital audio functions. In effect, it permits the drive to act as a port replicator for the Audigy's S/PDIF connectors.
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