What is a CD, really? It’s a bunch of digital music files on a disc. Why not eliminate the disc, put the music files on a computer’s hard drive, and play the files via your computer rather than through a CD player? That’s what computer-based audio is all about.
Once you have a computer, music playback software, and storage for your music files, you need a way to move the digital music files so they can be played over your stereo system. If your computer is near your stereo you can connect the computer to your system by one of several methods.
Because there are so many ways to get from point A to B to C, creating a comprehensive and totally up-to-date guide that includes every permutation of hardware and software available is nearly impossible. Instead this primer will explain and describe categories of software and hardware needed to accomplish the job along with a smattering of market-leading products.
Just as with analog audiophilia, the world of computer-based audio can be as simple or as complicated as you choose to make it. For some folks computer audio is an all-consuming hobby, while for others it’s merely another, more convenient way, to access their music libraries.
The Basic Building Blocks of Computer Audio
In computer audio the first and most obvious component is a computer. Computers come in two primary varieties—PC and Mac. Despite what competing commercials would have you believe, both are fully capable of working equally well as part of a digital music-delivery system. Which one is a better choice comes down to your personal priorities and budget.
Mac-based systems are ideal for someone who wants to keep life simple. Mac’s iTunes software was designed for the Mac and works seamlessly with other Apple devices such as the Airport Express, Airport Extreme, and Apple TV. The primary advantage and disadvantage of a Mac is that you have fewer options in terms of software and hardware. As you‘ve probably learned from Microsoft’s attack commercials, Apple hardware is more expensive, but not prohibitively so—a Mac Mini, which works very nicely for computer audio, has a base price with a 120GB drive of $599.
PC-based music systems are available in a mind-numbing variety of configurations and prices. Both the least expensive and most expensive computer-based music systems use a PC chassis. The differences in price are due to both hardware and software options, as well as how much customer support and initial set-up help comes with the system. With skills and patience you can literally build a music-server PC piece by piece, carefully selecting every component, at substantial savings over a similarly featured turnkey system. But given the nature of computers, doing it yourself will involve far more time and effort and the end result may still be less user-friendly and potentially less reliable than a completely preassembled system. Some especially computer-savvy audiophiles have built music systems based on Unix or Linux operating systems, but this is only for those who really love working with computers.
The music playback software you choose will have a profound effect upon the quality of sound you’ll hear from your computer-based music system. It also has a major impact on the ergonomic elegance of the system. As I mentioned earlier, with a Mac your options are more limited than with a PC. Most Mac users opt for iTunes, but there are other options including MPE Player, VLC Player, Real Player, and Audacity (which is also a very good recording program). If you go with a PC the list of music playback programs goes on and on. Almost every week there’s a new piece of software for music playback available.
Regardless of what flavor of system you chose, you need a place to store your music files. Hard drives have become so inexpensive that storage space has become infinitely expandable. Most computer music systems employ at least a pair of 500GB drives so that one can serve as a backup for the other. Hard drives can be mounted inside the computer or externally via USB, Firewire, or Ethernet connections. Recently SSD (solid-state or silicon) drives, which can replace moving-part hard-drive discs with physically static memory chips, have come down in price to where they are also a viable storage option. Since SSDs have no moving parts and generate no physical vibrations or heat some computer audiophiles feel they offer a sonic advantage over hard drives.
Some music lovers have the money, but neither the time nor the inclination, to assemble their own computer-based music system. Fortunately quite a few companies offer complete “turnkey” systems. One of the better-known options is Olive (olive.us). Olive offers units with built-in CD trays for CD ripping, a built-in hard drive, and provisions for multi-room wireless or wired setups. Its base unit, the Melody N2, is priced at $1499. Another company, Qsonix (qsonix.com) offers several models of music servers that will support up to 192kHz music files. Its Q105 2-zone system’s base price is $4450. Moving up the price ladder, Soolos (meridian-audio.com/product-model/sooloos-media-system.aspx) offers an ergonomically elegant system that uses a touch-screen 17-inch LCD to select music from its library as well as a proprietary metadata database which permits users to do exacting searches of their music libraries. A basic Soolos system starts at $12,000.
Now that you have a computer with your music inside and music software to play the music, you need to get the music to your audio system. One way is to put a digital-to-analog converter (DAC) card in the computer itself. Often called “sound cards,” these devices usually offer not only analog outputs but digital outputs as well. Many PC soundcards even support 5.1 or 7.1 analog for home-theater applications. The disadvantage of soundcards is that most were designed principally for gaming PCs and many use inexpensive DACs.
Some soundcards do have good DACs and excellent specifications, such as the $175 Asus Xonar Essence STX (usa.asus.com/products.aspx?l1=25&l2=150). This card features 124dB signal-to-noise, has a built-in headphone amp, and supports 192/24-bit files. It uses a Cirrus-Logic CS53811 ADC, and has swappable op-amps in the analog section, so you can try different ones to suit your tastes. It also employs extra shielding for the analog section to reduce the effects of electronic noise in the computer’s chassis. Unfortunately for Apple users, it’s only available for PCs.
A pro audio sound card such as the $675 Lynx L22 PCI card (lynxstudio.com/) supports high-definition music files and has additional shielding to protect it from the computer’s electronic environment, but obviously it costs substantially more than basic consumer cards. The good news for Mac users is that the Lynx card works in both Macs and PCs.
A second option is use an external DAC with a USB connection. Every modern PC and Mac computer has at least one USB output connection. USB DACS start at as little as $99 for a High Resolution Technologies MusicStreamer (highresolutiontechnologies.com). The MusicStreamer sounds remarkably good and is capable of decoding up to 48kHz/16-bit music files. On the other end of the price spectrum, Empirical Audio (empiricalaudio.com) makes a suite of products designed to work together or individually, including a dedicated USB DAC called the Overdrive DAC with USB ($3699 base price), an Off-Ramp USB converter so you can use S/PDIF DACs with USB-enabled computers ($699 base price), and a Pace Car re-clocker ($1250 base price) which is designed to reduce jitter from S/PDIF sources. Most USB DACs are limited to 48kHz and 16 bits. But there are some exceptions, such as the $495 Bel Canto 96/24 USB converter (belcantodesign.com), which converts a 96 kHz/24-bit USB stream to a S/PDIF coaxial connection. In the future even more companies will be offering higher resolution USB DACs.
Another option is to connect either a coaxial or optical/TosLink S/PDIF output from your computer to an external DAC. Apple offers optical TosLink outputs on every computer it makes. For PCs, soundcards can be installed that will supply coaxial and/or TosLink digital outputs. The nice thing about S/PDIF outputs is that they readily support higher bit rates. You can begin to enjoy higher definition (above 48kHz 16-bit) music files merely by connecting a DAC that supports these higher resolution files to the computer’s S/PDIF output. Some audiophiles believe that coaxial connections are inherently sonically superior to TosLink due to coaxial’s lower jitter. But a TosLink connection permits complete galvanic (electrical) isolation between a computer, which can be a source of EMI, power supply, and AC noise. This noise can affect the rest of your sound system. Whether one connection method is sonically better than the other depends as much on the other components (both hardware and software) in the system as the connection itself. Unfortunately for audiophiles who don’t want to experiment, can you only reliably determine which connection is sonically superior in a particular system by direct comparison.
The IEEE 1394 FireWire digital connection comes from the pro audio world, where it has been the standard for several years. All upper-end Macs are equipped with several FireWire connections. FireWire adapter cards can also be easily installed in any PC. Most FireWire devices include multichannel ADCs and DACs along with a multiplicity of analog and digital inputs and outputs since they were made for recording. But some FireWire audio devices were designed for two-channel use only, so they have fewer features. Market-leaders include the $495 Apogee Duet, $895 Mini-DAC, and $249 One (apogeedigital.com). Focusrite (focusrite.com) makes two reasonably priced full-featured FireWire devices, the $349 Saffire and $299 Saffire LE. Both come bundled with very nice recording software.
While many pro audio companies, such as Mark of the Unicorn (motu.com), PreSonus (presonus.com), Mackie (mackie.com), and others, make FireWire recording interface units that can serve as DACs in a computer-based audio system, the majority come with dedicated software packages. However, most pro audio devices will work with consumer playback software such as iTunes merely by designating the unit as the sound-output device in your computer’s sound control panel. Occasionally you will have to hunt on-line for a needed driver. On rare occasions a manufacturer may not yet have a driver for the latest generation of your operating system. Buying from a retailer who can give you phone and on-line support as well as let you try out a card in your system is important in guaranteeing satisfactory final results.
The last wired solution to connect your computer to your audio system is Ethernet or CAT-5 cabling. Ethernet wiring is designed to support long runs without signal loss so you can have your computer in one room, your hard drive with your music library in another, and your music system in a third room. Ethernet DACs start for as little as $99 for the Apple Airport Express (apple.com), which can be used either wired or wireless and has both analog and TosLink digital outputs. Microsoft X-Box 360 (xbox.com:80/en--US) or Sony PlayStation (us.playstation.com) game machines can also serve as Ethernet DACs since they both have two-channel analog outputs. Higher-end options include the $4200 Linn Majik DS Ethernet DAC (linn.co.uk), the $1995 Logitech Squeeze Box Transporter (logitech.com), and the $2876 Koetsu Blacknote DSS 30, $7200 DSS 50, and $12,800 DSS 50 Tube (koetsuusa.com). These higher-end Ethernet DACs also support higher bit rates, and some like the Linn will even work with 192kHz files.
If you can’t or don’t wish to use Ethernet cables to connect your computer to your music system, wireless Wi-Fi offers almost all of Ethernet’s capabilities. Wireless systems do have drawbacks when compared to a wired system, however. A wireless system will not be able to span as long a distance as easily as wired system and can’t support as much data. Computer cognoscenti refer to this as “having a smaller pipe.” Especially if you intend to listen to a lot of high-definition music files or HD video, a wired system will have fewer issues with possible dropouts and data transmission errors.
Still, for many music lovers a wireless-connected computer-based music system offers the easiest installation, setup, and day-to-day ease of use. This is especially true for the less technically sophisticated users in a household. The two market-leaders in wireless computer audio are the Logitech Squeezebox and the Sonos system. The Logitech Squeezebox product line (logitech.com/index.cfm/speakers_audio/wireless_music_systems) has five different versions, the $299 Squeezebox Classic, $399 Duet, $149 Squeezebox Receiver, the $1999 Transporter, and $299 Squeezebox Boom. All models require “Squeeze Center” software to be installed on your computer to access your computer’s music library, but they can access the Internet and utilize Internet-based music content even when your computer is turned off. The Sonos system (sonos.com) comprises four components: the $99 ZoneBridge, which connects the system to the Internet via an Ethernet connection; the $349 ZonePlayer 90, which streams music to a home stereo via its analog or S/PDIF outputs; the $499 ZonePlayer 120, which has a built-in 55W RMS two-channel amplifier so it can directly drive speakers; and the $399 Controller, which can run any and all Zone-players in your home. The Sonos system does not require your computer to be on to access your music library, but it does need one of its components to be hard-wired to your Internet modem. It is also a “closed” Wi-Fi system, meaning that it operates on its own Wi-Fi network that’s independent of other Wi-Fi networks you may have in your home.
Yamaha recently unveiled its own wireless music system dubbed the MusicCAST2. The MusicCAST2 system consists of the $499 Network Music Commander model MCX-RC100, which is a remote control with a full-color LCD screen, and two Network Music Players, the MCX-A300 and MCX-P200 ($399 each). The A300 has a built-in amplifier so it can drive speakers while the A200 is made to hook up to an existing system via line-level or digital outputs.
At a substantially higher price point (price TBA) Thiel (thielzoet.com) debuted its Zöet multi-room, multichannel music system. It supports 5.1 channels and uses a central unit called the dB1 to process and distribute audio via a closed Wi-Fi network to powered Thiel SCS4D speakers and SS1D subwoofers in various rooms. A single Zöet remote controls source, volume, and music mode for any and all other Zöet components.
Of course, most of your music doesn’t start off as downloaded digital files on your computer. There are two principal methods for importing digital music—ripping CDs (I’ve always hated this phrase as it implies that you’re doing something illegal by copying your own CDs) . To “rip” a CD you need CD-ripping software and a CD/DVD drive that can read your CDs. The iTunes software has a CD ripper built in. But some enthusiasts feel that dedicated stand-alone CD ripping software does a better job, despite the lack of any conclusive data proving that third party ripping software has fewer data errors. Many PC owners use Exact Audio Copy (exactaudiocopy.de/en/index.php/overview/features/introduction) to do their CD ripping or Foobar2000 (foobar2000.org), which is a freeware audio player for the windows platform that also has a built-in ripper.
Once the CD has been ripped it must be organized into folders so your music-playing software can locate it. Once again iTunes does this automatically once you have designated a location for its music library. Foobar2000 also has a complete set of organizational options.
Many old-school audiophiles have extensive collections of music on LP they want to add to their computer audio digital music library. Copying LPs can be as simple as playing a record on your turntable and having the signal go directly from your phono preamp into your computer via a soundcard’s analog inputs, or a multi-stage process involving specialized pieces of hardware and software. TAS Issue 177 has a primer that goes into the process in detail.
Downloading a digital music file is as easy as downloading any other digital file from the Internet. Just like other software files, you can acquire it legally with the full rights and privileges of ownership, or clandestinely via less than legal means. Naturally, I recommend the former. Digital music files come in all flavors from 64kbps (kilobits per second) MP3s to 192kHz/24-bit high-definition files. Generally the higher the bit-rate, the better the music will sound.
On-Line Music Sources
Computer-based audio systems not only let you play your own digital music library, but also open up a universe of on-line music sources. One of the most diverse sources of music is Internet Radio. Not only do almost all commercial and public FM and AM radio stations have “streams” of programming available, but also Internet-only radio stations have proliferated in recent years. Streaming a radio station is as simple as logging into its Web site and clicking on the “listen” button. Usually you will need to download a “marker” that will allow your music playing software to find and play the stations current programming. Some stations give you an option of iTunes, Microsoft MP3 player, Real Audio Player, or generic WAV streams. Some also offer more than one quality level such as 32kbps for basic and 128kbps for higher-quality sound.
Many radio stations that regularly broadcast radio programs such as Prairie Home Companion (prairiehome.publicradio.org) also have podcasts of entire shows, which you can download for later listening.
Other Internet music sources are personal jukeboxes such as Rhapsody, Pandora, and LastFM.com. Each of these services allows you to create profiles that reflect your personal musical tastes. Some, such as Pandora, let you develop as many different “stations” as you wish. Each station includes different music depending on your mood. Once you create a station, which can be an artist’s name or a particular song, Pandora will play music based on its own proprietary search criteria. Every selection gives you an option of liking, disliking, deleting, or saving the cut. Using this methodology you can develop a unique station after only a few hours of listening. Pandora and Rhapsody have both free and paid versions (the free versions have commercials and more limited options) while Last FM is a totally free service.
Commercial Internet Music Sources
The largest retailer of downloadable music is the iTunes store. It offers not only music but also video and first-run movies. Music purchased via the iTunes store is often in MP3 form, but more and more music there is also being offered in 44.1/16 CD-qaulity WAV or AIFF files.
Amazon (amazon.com) also sells downloadable MP3 versions of many CDs. One of the best features on Amazon is the “play sample” option, which allows you to audition many CDs and MP3 files prior to purchase. Microsoft has its own on-line music store (music.msn.com), which offers MP3 music files and video material. MSN Music’s genre choices are spotty—it has Celtic and Cajun, but no Bluegrass, Americana categories.
Many record labels have developed or are developing their own on-line music stores. If a particular label has music you especially enjoy I suggest checking its Web site to see if it offers or is planning to offer digital delivery of its titles.
Sidebar: High Definition Music via the Internet
Although CD-quality digital music files are often mislabeled as “high-definition,” true high-definition files must be more than 44.1/16-bit Red Book CD resolution. Currently several sites actually offer true high-definition music, and many more will be coming on-line in the near future. Here is a list of current high-definition purveyors.
Musical genres: Classical, jazz, pop, rock, country, folk, bluegrass, Americana, world, New Age, blues, audiophile
Resolution: 44.1/16, 88/24, 96/24
Formats: FLAC, AIFF, 320kbps MP3
Prices: Single 96/24 track, $2.49; entire CD 96/24, $15.98 (same price for 88/24); single 44.1/16 track, $1.49; entire CD, $11.98
Payment: Charge cards
Best/worst features: Each CD comes with cover art in PDF form, meta-data is no more complete than a standard CD burned from a computer. On some obscure titles you may have to hunt for the cover art to insert in iTunes.
B&W Music Club
Musical genres: Classical, adult rock, world music, audiophile
Resolution: 44.1/16, 96/24
Formats: ALC, FLAC
Prices: Subscription is $59.95 per year (one new title is available with your subscription per month)
Payment: Charge cards
Best/worst features: Free trial. Music is unique and unavailable elsewhere, but the choices are limited to these titles.
Hi Rez Music
Musical genres: Indie rock, Americana, roots rock, jazz, classic rock, blues
Resolution: 96/24, 192/24
Formats: DVD, CD by mail
Prices: $21.99 per title
Payment: Charge cards
Best/worst features: All discs are at least 96/24, but most have been re-mastered from 44.1/16 and 48/16 masters.
AIX Records and iTrax
Musical genres: Classical, blues, jazz, acoustic, folk, audiophile
Resolution: 44.1/16. 48/16, 96/24, 192/24, DSD, DXD
Formats: MP3, Dolby Digital, DTS, WMA Pro, WMA Lossless, uncompressed PCM at 96kHz/24-bits
Prices: $.79 to as much as $2.99 per song
Payment: Charge cards
Best/worst features: Many format choices. Selection limited to several audiophile labels including AIX, SFS Media, and 2L.
Musical genres: Classical, jazz, folk, pop
Resolution: 320kbps MP3, 44.1/16, 96/24, DSD, SACD, HDCD
Formats: LP, CD, SACD, MP3, Studio Master 192, Studio Master 5.1, FLAC, WMA
Prices: 96/24 disc, $29; 44.1/16 disc, $15; MP3 disc, $12; Single selections, $1.70
Payment: Charge cards
Best/worst features: Good selection of classical and SACDs. Not much rock or pop music.
Musical genres: Classical, jazz, pop, rock, country, folk, bluegrass, Americana, world, new age, blues, audiophile
Prices: $12.99 per CD as well as library packages of multiple CDs.
Payment: Charge cards
Best/worst features: Needs Windows explorer or Windows Media Player to access its store. Currently in receivership with a less than rosy future.
High-Definition Tape Transfers
Musical genres: Classical and historical classical recordings
Resolution: 44.1/16, 96/24
Prices: Individual selections, $3; 44.1/16, $12.00; 96/24, $19.99
Payment: Charge cards
Best/worst features: Many rare classical performances from live concerts and discontinued labels, but quality can vary depending on the original source.
Musical genres: Classical, jazz, audiophile
Resolution: 44.1/16, 176.4/24
Formats: CD, HDCD, DVD-R HRx high-rez computer files
Prices: CDs, $12.98 to $16.98; HRx discs, $45
Payment: Charge Cards
Best/worst features: Catalog limited to Reference Recordings. All recordings were made using a very high quality recording chain.
Musical genres: Classical, jazz, world, audiophile
Resolution: 96/24, 192/24
Formats: WAV, AIFF, FLAC, MP3 (Lower rez files can be downloaded but Studio Reference Master Disc is mailed, no downloads)
Prices: $9 to $20 depending on format and resolution
Payment: Charge Cards.
Best/worst features: Unique material but catalog is limited. All titles have many resolution options.
Blue Coast Records
Musical genres: Folk, jazz, new age, acoustic, blues, audiophile
Resolution: 44.1/16, 96/24, DSD
Formats: WAV, SACD
Prices: CD, $20; SACD, $40; CD-quality singles, $2; high-rez singles, $4
Payment: Charge Cards.
Best/worst features: All recordings by Cookie Morenco. Occasional high-rez downloads of live studio concerts. All Blue Coast recordings have excellent fidelity but the catalog is small.