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RSS feedsWhat's the difference between recording, writing and burning a CD?
Give yourself a gold star if you know they all mean the same thing, but it's small wonder that even experienced PC users get confused by the amount of jargon surrounding this increasingly popular activity.
The good news is that most of the doubletalk can be ignored. Just because the law compels the makers of CD drives to invent new names for ideas that they have 'borrowed' from other companies doesn't mean you have to remember them all.
All you need to know are a few key concepts and techniques and you'll be able to record CDs like a pro, whether you want to make audio CDs, back up commercial discs and programs or simply store photos, MP3 files and videos as cheaply as possible.
If you're baffled by buffers and dying to know about dyes, read on - all will be explained.
The write stuff
Only one CD-RW disc is sold for every 80 CD-R discs. People prefer CD-R discs because they're cheaper, take less time to record and are useable in just about any device that can accept a CD.
A blank CD-R is little more than a layer of dye with a reflective metal backing, encased in a plastic sandwich.
As the disc spins, the laser head moves across it following a spiral track. The laser is turned on and off with great precision to super-heat the dye. Where the laser melts the dye, it becomes darker and the pattern of dark and light areas can be interpreted as binary data.
Not all CD-Rs are equal and you can't expect the very cheap ones sold in bulk to be as perfect as individually packaged brand-name products, but you don't have to pay through the nose for good discs.
A small number of manufacturers and licence holders produce all the CD-Rs that are sold under thousands of brand names and some of the cheaper ones can be just as good as the dearer ones. If you find a cheap brand that works well in your drive, stick with it.
Book Burning
You can turn a blank CD-R into almost any kind of digital disc, depending on how you arrange and record the information to it.
The original music CD standard uses the CD Digital Audio (CD-DA) format. This is enshrined in something called Red Book.
When the CD-Rom came along, its format was published in Yellow Book and new books in new colours have been published for each new development in CD technology.
The Yellow Book format became an international standard (ISO9660) and is still used for commercial program distribution discs.
ISO9660 discs can be created using popular recording programs such as Ahead Nero or Easy CD Creator but for convenience, it's better to record a modified ISO disc that can contain more folders and long file names.
Joliet is just such a modified system. It was devised by Microsoft to make the most of Windows 95 and is an option in all good recording programs.
The data on an ISO CD-Rom can be anything: text, applications, images, video or music. As long as you have got software installed on your PC to view or play each type of file, you can mix them freely on the disc.
If, however, you want to make a disc that will work in a home DVD player, it must conform to the White Book's Video CD (VCD) standards.
Similarly, audio CDs for playback on CD players must conform to CD-DA standards, though there is an interesting variant called a Mixed-Mode CD in which the first track contains ISO data for CD-ROMs and the other tracks can be played on a CD player.
None of this is as complicated as it seems. Mostly you'll stick to CD-DA for standard audio CDs and ISO for data files and MP3s. You'll only need to dip into the many other formats if you get serious about CD recording.
Packet in
If you're a Windows XP user, you can record CDs without additional software.
Just drag files into your CD-RW drive's folder and when you're ready to record a CD, click an icon on the Windows Taskbar. Although this is a good way of archiving files, it doesn't replace a proper recording program.
Windows XP uses a system called packet-writing to store individual files, but it can't make exact copies of CD-ROMs or audio CDs.
Another restriction is that the Windows Media Player can only rip audio CD tracks into Microsoft's WMA format, not the more versatile MP3 format used by many portable music players.
Packet-writing has never really taken off but this might change when the Mount Rainier standard becomes established. This requires a suitable drive (look for Mount Rainier compatibility if you are buying a new drive) and special software.
Mount Rainier does not require discs to undergo lengthy pre-formatting before use and has the potential to produce discs with fewer errors and less wasted space.
Speed isn't everything
Remember that the recording process is the final and shortest stage of recording a CD.
Prior to recording, you must assemble the data on your hard disk. If you're making a music CD, you will want to determine the playing order.
This done, you're then ready to write the disc and given the time this takes, the fact that a 48-speed drive creates a CD twice as fast as a 16-speed drive is almost irrelevant.
The reason why a 48-speed drive isn't three times as fast as a 16-speed drive is that the maximum writing speed is only achieved at certain times.
A CD spinning at Constant Angular Velocity (CAV) rotates at the same speed all the time. This means the outside edge of the disc is spinning faster than the inside and so writing gets quicker as the laser spirals out towards the outside edge of the disc.
The alternative to CAV is Constant Linear Velocity (CLV), which was common until drives exceeded the eight-speed barrier.
With CLV, the rate of rotation varies as the laser head moves across the disc to maintain a true and constant recording speed, but it's an impracticable technique for today's high-speed drives.
Instead, they use the hybrid systems of P-CAV (Partial CAV) or Z-CLV (Zoned CLV). Both types of drive are fast but neither is able to deliver a drive's maximum quoted speed at all times.
A word of caution on ever-higher read and write speeds. There have been reports of CDs 'exploding' into fragments in 52-speed drives.
Such incidents are isolated and tend to involve commercial games discs that have been run at high speeds for long periods.
Experiments conducted in 2001 for RM Computers established that an intact disc is unlikely to break apart at 52-speed but warns that discs with surface cracks longer than 6mm could explode into fragments at this speed.
At 40-speed, the risks are minimal, which is why Plextor's latest 48-speed writer is factory-set to operate at 40-speed unless overridden by the user.
Coaster toasters
Given the high spin speeds involved in recording a CD and the need to accurately place the laser for each burst of power, it is essential to keep data flowing smoothly.
If the flow is halted, even momentarily, the resulting gap on the CD-R could turn it into a useless lump of plastic, traditionally referred to as a 'coaster' (because a drinks mat is all it's good for).
To keep the production of coasters to a minimum, CD-RW drives have built-in memory - a 'buffer' - that's topped up with data while it's being simultaneously emptied for writing.
That way, if the data supply stops for any reason, the CD-RW drive still has data in the buffer that it can use until the supply resumes.
However, if your PC fails to keep the buffer topped up, a 'buffer underrun' occurs and you end up with yet another coaster.
Sanyo came up with a solution for this late in 2000 with its BURN-Proof (Buffer UnderRuN-Proof) system, enabling a drive to stop recording a disc when it is short of data, then to resume at the same point when the data flow is restored.
Today, only the cheapest drives fail to offer BURN-Proof technology or one of its many proprietary equivalents: Exac-Link, Flextra-Link, Just-Link, PowerBurn, SafeBurn, Seamless Link, SmartBurn and Super-Link.
Beyond burnproof
In the quest for the perfect burn, some Plextor drives use 'PoweRec', a system that constantly monitors the writing process, varying the recording speed and laser power to ensure the best results, but at the expense of speed.
Another Plextor innovation is 'VariRec', which lets the user change the power of the laser during audio CD writing to prevent jitter and increase audio quality.
Yamaha's AudioMaster achieves the same ends by using oversized laser bursts to make discs easier to read in older audio CD players and improve sound quality. The downside is that the playing time of a standard CD-R is reduced from 74 minutes to 63 minutes.
Some Yamaha drives have a gimmick called DiscT@2, which records monochrome text or graphics onto unused portions of the CD's recording surface. It's certainly clever, but we're not sure how useful it is.
All burned out
With all this information digested, you can consider yourself a bit of a CD-writing expert. Whether you record 10 discs a day or one a month, making the most of the technology will ensure the best burns every time.
10 tips for successful recording
1. Close all running programs.
2. Disable any screensavers.
3. Disconnect from the internet.
4. Don't use your PC for anything else while recording CDs.
5. Find a reliable source of blank CDs and stick with it. There is no way to tell how good a disc is from its wrapper.
6. Don't use the maximum write speed of your drive. Drop down a couple of notches for increased reliability.
7. Make sure your recording software supports all the features of your drive.
8. Don't write files directly to the CD. Always create an image on the hard disk first, then record that to a CD.
9. It may be possible to update the firmware inside your CD-RW drive with software downloaded from the manufacturer's website. This procedure can irreversibly trash your drive if it goes wrong, so don't attempt it unless the manufacturer recommends it.
10. To make audio CDs that can be played in a conventional player, make sure you choose the option in your recording software to 'finalise' the CD.
The right side of the law
A practical thing to do with a CD-RW drive is make a backup copy of a game or audio CD in case you damage the original.
Of course, it is illegal to give away or sell such copies but soon you might not be able to make them at all because an increasing number of CDs are being specially manufactured to prevent duplication.
Macrovision, the company that invented the system that stops you copying commercial VHS tapes and DVD movies (try it and you'll see what we mean), also sells copy protection systems for CD-ROMs, including games.
Its SafeDisc technique uses special equipment to create a digital 'signature' on the glass master disc from which commercial CDs are pressed. Using a CD-RW drive, you can copy the data from the CD but not the signature and without that, the CD won't work.
Until recently, the majority of audio CDs have not been protected against copying, mainly because the leading protection mechanisms (SafeAudio, Cactus Data Shield and MediaCloQ) all suffer from the disadvantage that even factory-produced discs don't work on every type of CD player.
Despite this, a number of protected audio CDs have been released and even though some were subsequently withdrawn because of playback problems, there's no doubt that protection will one day become the norm.
In the past, every form of copy protection for computer media has eventually been broken. In fact there are websites such as www.gamecopyworld.com and www.cdmediaworld.com where you can find out how to copy protected discs and download programs to help you do it.
These sites survive because, at present, it is illegal to steal intellectual property but not illegal to tell people how to copy it for themselves.
All this is due to change when the UK implements its version of the European Copyright Directive which was due to happen late last year.
Once implemented, if you're caught copying a CD you can be sued, but if you tell somebody else how to do it you can be charged with a criminal offence.
Contacts
Ahead Software
No UK number
www.nero.com
Plextor
No UK number
www.plextor.be
Roxio
No UK number
www.roxio.de
TDK
CCL Computers, 01274 471273
www.cclcomputers.co.uk
Yamaha Europe
01525 289300
www.yamaha-online.de
See also:
DVDs offer loads of advantages when it comes to storing data. We expain all the ins and outs of writing DVDs, disc compatibility and DVD-writing software 30 Sep 2004
Buying branded recordable CDs and DVDs could hit your pocket hard. We ask whether it's worth paying for a name 14 Jul 2004All Peripheral Devices
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