Extract From Byte Magazine - Oct 29 - In the Air

[Steve Bildermann]

As Byte is now a subscription service I thought some people might enjoy reading some extracts.

RAID and Backups

After mentioning RAID in last month's column, a reader emailed to say he was perfectly happy with his mirrored drives using Intel's motherboard RAID. My reply was that on board RAID was a fine start, but it wasn't going to protect you against a power supply failure frying both drives; accidental deletion; or system theft. Chaos Manor has been hit with both of the first two, and my son Richard had his laptop stolen out of his truck out back. So, I wouldn't consider two drives in a single case to be an adequate backup.

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[Steve Bildermann]

Of course, I'm more paranoid than most, and so I end up saving everything I write to four or five places, press copies on passersby, and send another to Elbonia for something like safekeeping. You probably don't have enough PCs to save everything five times, but you certainly have options.

What media to use? Tape is rapidly becoming an option only for the high end; CD (or, if you have one, DVD) burners are the obvious first choice. There are over the Internet backup options, but they're not inexpensive. Windows XP does have a relatively simple way to cause backups to be written to a CD, though you probably want a third party application like BackupMyPC or Nero Burning Rom to manage this more simply. In any case, don't trust all your data to a single computer, even if it has a RAID array.

An afterword on tape: It's messy, it's inconvenient, tape can be expensive, but overall it's pretty cheap compared to losing your data: and tape is orders of magnitude more reliable than most optical media. This isn't so important if your data are mostly text where bit for bit accuracy isn't so critical; but with numerical data that's another story. It is precisely the need for data reliability that brought about the invention of DVD RAM, still by far the most reliable of the rewritable DVD options (and also increasingly hard to find). Travan and OnStream are good tape units, and if you have a lot of valuable data, tape may still be your best option.

ATI 9800, Heat, and the Antec Sonata

For a good general purpose system at the price, it's hard to beat the Intel D865GBF motherboard, as fast a Pentium 4 as most of us can afford it will do fine with a 2.53 GHz chip, and FSB speeds of 533, but better of course is a 3+ GHz chip and 800 bus speed and a good ATI video card. The D865GBF comes with Intel video, which is all right, but nothing to shout about It will play all the games I have tried it on, and it does fine, but it's not as pretty as the ATI 9800. Of course few things will be.

ATI has about the nicest text in the business. Matrox may do a little better, but Matrox boards are hard to find, and you don't want one if you play 3D games anyway. ATI boards put up really good looking text, and have gorgeous color, light, and shading in both 2D and 3D; in a word they are hard to beat. All the ATI RADEON boards from the 9100 up are good enough for just about anything you can do now. They all have great text. They all use pretty much the same drivers, so apart from the on board processing speed most machines see them as the same board. The All In Wonder versions do TV as well as computer video. Clearly if you want the latest and greatest you need the ATI 9800, but you won't be unhappy with any 9100 or later RADEON in a D865 system.

The D865 has built in sound that so far as I am concerned is as good as you'll get from the far more expensive sound boards, and the Jack Sensing system lets you set up 5.1 channel sound without problems. Of course there are only the 3 jacks, so you won't be doing recording if you're using those jacks for output.

If you want more conventional sound processing capability, I recommend the Hercules Digifire 7.1, which has all the conventional jacks, and works just fine with a D865; but of course if you aren't going to use either the sound or the video on the D865, you may as well get the Intel D875 motherboard and be done with it. You won't regret either.

I built my D865 in the Antec Sonata case, and it's the quietest machine in the house. Antec got a great deal of this right. Alas, when it comes to leading things out to the front panel, Antec put in all the wires, but their "plug" for audio is a mirror image of the pin layout on the Intel motherboard. You can't use it. Fortunately their hydra headed cable has individual wires as well as the consolidated plug, and Intel gives the pinouts, so you can hook up both USB and Audio to the front panel. It's tedious but I was able to do it, and it all works.

The Antec Sonata case is well designed, with good bays and racks for disk drives. It's very quiet. It comes with the "TruePower" 380 Watt power supply that so far has delivered more than enough power for any system I have put into it.

It has one problem: The fan is very quiet, because it is large and slow moving, and it's right at the edge of not being powerful enough when you put in an ATI 9800 video board. If you run a fast system with the 9800 in a Sonata with the case left open, it will definitely overheat. I left the new system on its side with the case open, and I got warning beeps from the Intel Active Monitor program that comes with the motherboard within minutes of running a complex video game in the system.

There are two remedies. One is to set up a fan that blows down across the ATI 9800. That stopped the warnings. The other, of course, is to close the case. This gets the air flow moving properly, and with the case upright and closed I haven't had any of those warning beeps, even in the middle of a huge battle in Dark Age of Camelot.

The buttoned up case does get a bit warm. Not hot: just noticeably warm, rather than the cool metal feel most computers have. Heat transfer to and out of the case probably helps with the heat dissipation, because, as I said, with the case closed I've had no temperature warnings even with fast action games causing the ATI 9800 to work hard indeed.

It isn't obvious, but there is a way to mount a second fan in the front of a Sonata case; the Antec manual says you should direct that to blow into the case rather than install it as an exhaust fan. With two fans this ought to work even with a fully loaded system, although it will probably be a bit noisier. So far I've managed with the one fan, and it sure is quiet.

Audio: Inputs and Outputs Count

I've talked about PC sound cards since there were PCs, though more in the last six months than in the five years previous, because I've been fortunate enough to have some new sound gear to try out. This month I want to talk about the input side of the sound game, after a little background on output.

For most people's uses, the PC's built in audio output is Good Enough. Certainly, in any room with a conventional computer humming away, it's difficult to hear the difference between the motherboard SoundMax audio and a consumer level add in 6 or 8 channel sound card. For most people, the big difference is in how many channels they have. This is the same reasoning behind $30,000 per screen sound in movie theatres: Sound is the transporter of story, even if most movies confuse "loud" with "good." A few motherboards are available with on board tube (yes, vacuum tube) amplifiers, the better to get that "warm" tube sound, but I don't expect that idea to sneak into more than a few tiny niche markets.

For PCs, surround sound has crept into the base model motherboards, since it's absurdly cheap to implement. The Intel brand 865 motherboards (and probably most of the licensed ones) support it directly. Software is starting to catch up; a lot of games (particularly one player) are starting to support surround sound, the better to make you jump when the monster sneaks up behind you. Few on line multi player games do, today, but they're starting to.

As I've also talked about in the past few months, connecting your computer to your speakers is its own set of fun. Stereo or even four channel surround (some of us remember when that was called "Quadrophonic" or just "Quad") is most usually connected directly to 2 or 4 powered speakers, or to a single amplifier and then to speakers. But: when you want to use your home stereo for six channel surround (known as "5.1," meaning five full range audio channels plus one bass channel), it's either through a bundle of six individual RCA cables, three stereo pair cables, or one digital connection.

Why digital output? The inside of your PC is a lousy place to convert digital signals to analog. Modern computers have any number of sources of Radio Frequency Interference (RFI), running at everything from a few dozen Kilohertz to hundreds of Megahertz. If I forget this, the old Pentium/3 system in the other room provides a regular click Ka POP! through its speakers to remind me.

Even with better than average engineering to minimize interference, RFI results in hum, hiss, or just plain lousy sound. Even without the fabled "Golden Ears" of the esoteric audio set, the average bloke can hear that stuff, assuming the background noise of the PC's fans, hard drive, and DVD player spinning isn't too loud.

The digital connection itself comes in two flavors, electrical and optical. The electrical version is "Digital coax," which looks like a standard RCA connector but uses a special coaxial cable. The optical "TOSlink" connector uses a plastic fiber cable, about which more in a minute. On some equipment, the two are collectively labeled "S/PDIF," which stands for "Sony/Philips Digital InterFace," or sometimes just "Digital." Most of the time, these connectors Just Work, taking in (or outputting, sometimes either, under software control) two channel digital audio.

Notice that neither of these connection standards matches the ones used for outputting from PCs to speakers. Both are commonly found on standalone DVD players and modern stereo amplifiers, since they come from the consumer electronics world.

Both Digital Coax and TOSlink can carry two channels, uncompressed, at a 44.1 KHz sample rate, meaning it's sampled 44,100 times a second, to a depth of either 16 or 24 bits per sample. The more samples, and the more bits per sample, the more accurate a reproduction of the sound there will be at the other end. This assumes accurate analog to digital conversion, and back again, a minefield of fact and conjecture among the Hi Fi Gang that I'm going to tiptoe around.

The 44.1 KHz rate isn't one any computer literate person would have chosen. It comes to us courtesy of the CD audio standard; the more power of two friendly number, 48 KHz, is used on more professional audio gear. I say "more professional" because the state of the art in recording studios is 96 or even 192 KHz (which you'll notice are even multiples of 48 KHz, making down conversion mathematically simple).

Neither Digital Coax and TOSlink have any smarts to speak of. There's no back channel, no way for the receiver to negotiate with the sender for the formats it can take. A computer geek might wish for a USB 2.0 or FireWire connection, where some intelligence (and error reporting) might be added. During WinHEC, the Microsoft audio wizards talked wistfully about such a standard emerging, but the consumer electronics world gave up on both after five years of trying and selling almost no units.

What's It All Mean?

If you want to record spoken word from a single person, and don't care too much about quality, your PC and a microphone are all you need. Roberta recorded all of the narration for her TLC Reading Program this way, with a single mic plugged directly into the "Audio In" on her PC's Sound Blaster card. She used Sound Forge 4.5 to record and edit the 4,000+ phrases, then compressed them down to 11 KHz mono samples to fit on a single CD along with the program. The results have helped kids learn to read for some years now.

If she were starting this project now, we would probably use a better microphone and an external analog to digital converter, fed into her PC. Not only would this offer a quieter (read: less noise) version of the audio, but less noise means the resulting audio would compress better, too. We'd use Sound Forge 7 to record and edit the samples, assuming that Sony hasn't completely messed up Sound Forge after they bought it.

Of course, if you want to record, say, a piano and guitar duo, or even your son's rock band, it gets a little more complex. I won't deny you the peculiar pleasure of treading through all the craft, science and lore of audio recording, when literally hundreds of Web sites and paper publications will support your quest. Certainly, anyone wanting to capture anything more complicated than spoken word should invest a little care; it's not just about good microphones and placement, but knowing something about the subject. That said, here are a few suggestions.

Our current choice for external, inexpensive analog to digital is the Echo Digital Audio Gina24, which combines an external interface box with a half length PCI card. It supports two analog microphone inputs and 8 analog outputs for surround sound. It supports 8 simultaneous digital inputs and 16 outputs. It has a headphone jack with a volume control. Just as importantly, it will mix all of these inputs live, in hardware and output them to all of the outputs. I haven't had good hearing since 1950, but those with more of a right to an opinion than an old cannon cocker say that the Gina24 is quite low noise, certainly more than Good Enough for most home recording.

The Gina24 also offers an ADAT in/out, the 8 channel version of the TOSlink connection. Actually, the connector pulls double duty; you choose in its driver whether it's supporting TOSlink or ADAT, depending on the gear you're connecting to. So, if you have appropriately equipped gear, you can use ADAT to transmit 8 simultaneous channels of audio to or from the Gina24, neatly tying you to the pro audio universe without having to learn many of its peculiarities. And the Gina24 can be ganged, two or more cards to a single PC, if you need more channels.

For software, unless you need something truly advanced, we haven't found anything on the PC which beats Sound Forge. 6.0, the current version (7.0 is just weeks from release), offers just about everything you need for stereo recording. Magix's Samplitude is the next step up, an application with nearly every feature a professional audio engineer could want in software, including native support of surround sound mixing. Samplitude can, for instance, feed completely different mixes to every performer's headphones, live, while simultaneously recording up to 99 audio tracks. Be warned that Samplitude is not for the faint of heart, whereas a PC savvy user can learn enough Sound Forge to get going in an hour or two. That's not to say the sound editing universe is so limited: Adobe is going to give Sound Forge a run for its money with Audition, their new audio editing application; Avid's ProTools continues to be the leader for professional recording on the Macintosh.

And for the amateur, Gold Wave remains the best deal in town: a cheap and relatively easy to learn and use sound editor with more features than most will ever want. Sound Forge is what the big time professionals use, but Gold Wave is the sound editor for the rest of us. Whatever path you choose, it is getting simpler and easier to edit sound on your PC all the time.