Get More 'Burn for the Buck' With Disc-Duplicators

While today's PCs and media software are great for making single-copy CDs and DVDs, they're not so great for making multiple copies. In this TechBuilder Recipe, I will make the case for building a dedicated CD and DVD copying box. I'll also show you two ways to build duplication towers.

For users who need to make multiple copies of CDs and DVDs, having a dedicated box is a powerful solution. A dedicated CD and DVD duplicator is reliable, fast, easy to use, and easy to maintain. It also produces more universally readable media than other methods.

This is an issue for both business and entertainment data. As you probably know, the ability to burn data to CD and DVD media marks one of the biggest data-storage advances in years. Today's capacities range from about 640 MB on a CD-R (the "R" means recordable) to roughly 4.7 GB on a DVD-R. Even greater capacities can be achieved with strategies like "overburn" and new technologies that use a second recordable layer ("dual layer"); these can extend a DVD disc's capacity to a whopping 8.5 GB.

Copying one CD or DVD at a time is no problem for today's fast machines and reliable burners. But if, for example, a user needs to get a parts list on CD to their top 10 wholesalers every month, or needs to distribute 50 copies of a sales-training video on DVD, then one-at-a-time is not the way to go. Besides being tedious, it can tie up one or more PCs--something many businesses cannot afford.

In this Recipe, I'll first outline the basics of CD and DVD burning. Then I'll explore the hardware and software-based options to meet your clients' needs. I'll also provide two recipes for building reliable CD/DVD duplication boxes, including tips on how to choose the components and configure the systems. When I'm done, you'll know how to build boxes that can copy today's CD and DVD formats quickly and reliably, getting your clients the most of what I like to call "burn for the buck."

Copying Basics

CDs and DVDs are used today not only for distributing movies and music, but also as an economical and manageable storage media for software, books, training courses, sales tools, buying guides, and more.

Basically, there are just three ways to copy a disc: Single copy, duplication, and replication. Let's examine each separately:

• Single Copy: Also known as a "one-offs," this is the process of making just one copy at a time on a PC or dedicated disk copier. Making one-offs is fine for backing-up data files and copying music files onto CDs for personal use. But for multiple copies, it's highly inefficient. Also, using a PC to make multiple one-offs while also running other applications can cause compatibility issues, or slow the system to a crawl.

• Duplication: Commonly referred to as "burning," this is the process of copying the contents of one CD or DVD to another disc using a drive with write capabilities. The PC etches the data onto a recordable CD or DVD disc with a laser small enough to be integrated into a normal PC drive bay. CD and DVD burners and media have been a runaway success due to their portability, convenience, and economy. This method is best for producing limited quantities of copies--more than one, but fewer than a commercial run. For quantities less than 500, many businesses "burn" their manuals, parts lists, and training videos in-house using either PCs with multiple burners or dedicated duplication machines ("duplication towers").

• Replication: This is a manufacturing process that essentially replicates or "clones" the original master. First, a "glass master" is created from the original. Then a set of molds, or "stampers," are made from the master. Stampers act as a blueprint for the replication process; they are mounted into an injection-mold machine, where a replica of the mold is created in the form of a 120-mm plastic disc. The formed disc is then coated with a micro-thin reflective layer of aluminum. Finally, the disc is coated with a protective lacquer that is first spun onto the disc, then hardened by ultraviolet light.

  Because replication is complicated, it's typically considered only for large runs of at least 1,000 copies. At those volumes, replication produces the lowest per-disk cost and offers the highest possible readability levels. In fact, all commercially distributed entertainment and software CDs and DVDs are produced using replication.

For many businesses, the best choice is duplication. Few businesses need to make 1,000 or more copies at a time, the minimum needed to make replication cost-effective. And many businesses need more flexibility than one-offs provide. Duplication, therefore, represents a good middle ground.

For these clients, a dedicated duplication machine makes good sense. These boxes, also known as "duplication towers," house up to 11 target drives, a hard disk on which to maintain the original source files, and the hardware and software to control it all. Duplication towers also offer good compatibility across a vast field of drives and systems. What's more, they can be set to repeatedly copy an image until the total number of copies desired is reached. Some towers even include robotic arms with magazines of 25, 50, or 100 blank discs so they can operate unattended.

Two Types of Duplication Towers

Duplication towers are typically built using one of two methods: Either as a PC-based system, or using a specially built piece of hardware called a duplication controller.

Here's a quick view of their relative benefits:

PC-Based:

• Can be used for other tasks (though not when duplicating)
• Easily expandable
• Good use for an older PC
• Wide choice of duplication software

Duplication Controller-Based:

• Fewer parts: no motherboard, memory, or OS needed!
• Simplicity of construction and operation
• Designed for optimal data throughput for fewer copy errors
• Compact size

While I'll discuss both options, this recipe will focus on the more flexible PC-based approach. I'll show you how to build a PC with multiple burners that is optimized for channelized data transfer between the disk and burners to avoid buffer underrun--the most common cause of copying failure. Before we start building, let's examine this important issue.

Why Bad Things Happen to Good Copies

The process of burning CDs and DVDs is not without problems. At the top of the trouble list is compatibility, or a lack thereof. The industry has adopted a large and growing number of disk formats and media types. This means that a disc that plays just fine on one machine may not work at all on another.

Also, problems inherent with the burning process can render a disk unreadable on some players. Anyone who has burned copies of their favorite music CD has probably had the experience of seeing "disk not found" or a similar error message when later trying to play the disk in their car or portable CD player. These disk duds are also known as "Frisbees"--good only for throwing.

Here's a breakdown of the current leading CD and DVD formats. Including non-recordable formats, I count a total of 10 that you need to at least consider:

Non-recordable Disk Formats
CD-Audio:CD disc with audio tracks in the CDDA (Compact Disc Digital Audio) format, which is the standard for recording music tracks on a compact disc.
DVD-Audio: An audio-only storage format similar to CD-Audio that can also contain music videos, graphics and other information
DVD-ROM: (Digital Versatile Disc-Read Only Memory): A read-only DVD disc used for storing data, menus, audio and video. Most DVD-ROM drives will play DVD-Video movies, but home DVD players cannot play DVD-ROMs.

Recordable Disk Formats
CD-R: The most popular format for writing discs, CD-R normally holds up to 700MB of information, but larger, less compatible discs are available up to 1GB. The discs are inexpensive and can be used to share data with any PC equipped with a CD-ROM drive.
DVD-R: DVD-R is similar to CD-R in that you can write to the discs only once. But it has much more storage capacity (up to 4.7GB of data). These discs are normally used for burning high-quality video to be played on a DVD player.
DVD+R: Similar to above, but is a competing format..
CD-RW: Unlike the CD-R format, the CD-RW format can be written to and erased multiple times. CD-RW drives read and write to either CD-R or CD-RW discs, but many older CD-ROM drives can't read CD-RWs.
DVD-RW: Like CD-RW, DVD-RW is a rewritable format and a rival to DVD+RW. The discs are designed to be used like a video tape and video can be recorded and erased and played back in a DVD player. The drive can also create CD-RW and CD-R discs...
DVD+RW: Similar to above, but is a competing format.
DVD-RAM: This special format comes both with and without a cartridge that contains a DVD disc. Think of it as a removable floppy disc with storage space up to 9.4GB. These discs can only be played in special DVD-RAM drives or special set-top player/recorders. With the best error correction and longer life than any of the other optical formats, it's ideal for storing and archiving data.

There are other reasons why burning can fail, too. The most notorious is a condition called "buffer underrun." It occurs when the buffer supplying data to the burner is emptied before all the data requested can be written. It happens either when data is interrupted or can't be supplied fast enough to the writing device. If the PC's software and hardware fail to prevent this situation, the disc is rendered useless. The good news is that there are several ways--using both hardware and software--to avoid buffer underrun.

Now let's start building our duplication tower. As I mentioned earlier, there are two main ways to go: PC-based, or duplication controller-based. Let's look at the PC solution first.

PC plus Software Solution

In general, I recommend IDE devices. If you have been building PCs for a while, SCSI might seem like an obvious choice for attaching multiple media devices. In fact, SCSI is used in building monster duplicating systems where data-bus control is critical. (For example, Nero software has built and tested duplication towers connecting 32 burners via SCSI.)

But IDE devices offer several advantages over SCSI. While SCSI may provide better control of more peripheral devices, IDE invariably wins out in price, availability, and ease in configuration. One serious limitation of IDE for this application is the limit of two devices sharing one channel with a Master/Slave relationship. To build a system with multiple IDE burners, you must use multiple IDE controllers, which use up valuable PCI slot real estate. Still, since IDE parts are so widely available and proven, I prefer IDE for systems with six or fewer burners. I only use SCSI for larger systems where cost is less of an issue.

Here's my parts list and considerations for a PC-based duplication tower:

• Motherboard: I recommend Pentium III / 400 MHz or better with at least 128 MB of RAM. (With requirements this modest, consider retooling an older PC as a duplication tower.) Remember that the number of IDE devices you can add depends on the number of IDE ports that are available. For example, many popular IDE controller cards support only two IDE ports. Depending on how many burners will be installed, you may need to obtain additional PCI slots.

• Hard Disk Drive: You'll need a 40 GB hard disk if the system will be used for copying CDs only, but a 120 GB drive for duplicating DVDs. Either way, partition at least OS and data partitions. Then, for the most expedient transfer to your line of burners, keep individual files or disc images on a data partition.

  The newer 7200-RPM drives are best for copying DVDs and achieving higher write speeds, though they're not necessary for CD duplication. Also, remember to defrag your disk often; it's one way to avoid burning errors (and see more tips below).

• IDE Controllers: As already mentioned, you'll need additional IDE controller cards to attach IDE burners. Each card supports two channels, and each channel will support one master device and one slave. I prefer adding additional controllers when possible, then configuring all burners as master devices; this achieves top speeds while still avoiding buffer underrun. SIIG's IDE controllers, such as the model SC-PE4B12 are know to work well for duplicating applications. Sadly, Promise IDE cards have had issues with duplication software, so I'd avoid them for this application.

  A word about cables: For best performance, use 80-wire IDE cables for all primary connections between the IDE controller and the DVD/CD burners or ROMs. These newer IDE cables have 80 wires--twice as many as the older cables--but still connect to 40-pin headers. Also, 80-wire cables produce faster, more accurate data transfers, which, in turn, support faster devices. Plus, the cost difference between 40- and 80-wire cables is minimal.

• Case: Look for a sturdy case with ample bays on the front. If you are building for four or more burners, choose a full tower for space. Some case manufacturers offer a "duplication tower" case that's ideal for this application; these cases include front-accessible bays with good airflow. Also, consider adding extra cooling if your duplication tower will be used in a production setting. Remember, these boxes are called "burners" because they actually use a laser to burn the disk. That creates a lot more heat than a normal PC.

  Finally, avoid running the system "open" or with case covers or sides off, even when testing. With the covers removed, air will not flow through the case as designed, and the system could overheat. Burners generate a good deal of heat, and they depend on fresh air being pulled through and around them to keep them cool. Proper air circulation is critical.

• Power Supply: You'll need a high-quality power supply to meet the demands of your system. A minimal system with a couple of burners will require at least 250 watts. Larger systems with additional fans would be safer with at least 300 watts, even more.

• Monitor, keyboard, and mouse: Standard equipment is adequate, as there are no special requirements here.

• CD/DVD ROM: As your source, this should be reliable and at least as fast as your target burner's speed. That way, it will help to avoid buffer underrun on occasions where you might copy directly from CD/DVD ROM to CD/DVD Burners. It is more efficient to burn from a disk image, so--other than to make the occasional one-to-one copy--CD/DVD ROMs are typically used only to load data onto a drive partition. For my tower, I chose Lite-On IT's Model SOHD-1673S 16x DVD ROM drive for both price and reliability.

• CD/DVD Burners: I recommend that, whenever possible, you use drives of the same make and model number. While a burner is not strictly necessary, you will enjoy a distinct advantage by using drives of just one type. This will guarantee the same buffer sizes and buffering strategy. All the burners I've seen from major manufacturers perform well and are reliable, and I've seen little difference among them. Also, some burners, including the Lite-On SOHW-812S Dual DVD+RW Writer, have a 2 MB cache and employ buffer handling to prevent a buffer underrun condition. (Lite-On calls its buffer-handling feature Smart Burn.)

• Application Software: My pick is Nero's latest, Nero 6 Reloaded, which is available as part of Nero's Ultra Edition. Like most commercial copy software, Nero creates a hard-disk image of the CD or DVD you will be copying. It then buffers the data while it initiates the writing process to your line of burners. This is carefully orchestrated so the data arrives at the burner on time to avoid buffer underrun. Nero also recognizes the various buffering strategies of the burners and configures itself accordingly.

  Nero is an obvious choice for software; the vendor has a long-standing reputation as the leader in the field, and it performs significant testing with multiple burners. Also, with Nero 6, users get support for up to four target burners and can purchase a software key to turn on support for more.

• Operating System: I chose Windows XP Home Edition since no special features or networking are required. For optimal performance on the duplication software, configure Windows for the maximum size for PageFile under System Performance. Also, avoid using WinME and Win95 to run your duplication towers, as these two OSes are known to have difficulty handling the duplication processes, buffering, and multiple controllers required for making disc copies.

Assembly Tips

In most respects, assembling your duplication tower will be the same as a standard desktop solution--just with more burners. But you will need to do some careful planning regarding your additional IDE controller cards, burners, and cabling. After all, you'll have more devices and more cables than usual.

Once you've gathered together your parts and you have removed the cover from the case, plan the location of your IDE controllers, burners and cabling before configuring and installing any drives. Make sure all cables are long enough and that they can be dressed to promote good airflow.

Next, configure the motherboard, but install the processor, fan, and memory before installing the motherboard in the case. Install all additional IDE controllers and cables to the CD/DVD burners and ROM. Minimize cable clutter by keeping data cables flat along flat surfaces, gently folding and securing them to allow plenty of airflow through the case.

If, after a thorough visual inspection, you are satisfied with your system, it's time to connect your peripherals, power up the system, and do a BIOS setup. Create OS and data partitions on the hard disk, and your assembly is complete. You are now ready to move on to loading the OS and application software onto your duplication tower.

Once again, airflow is critical. So make sure the case has all its covers on before you do any significant or prolonged testing of the burners. Prolonged testing without the covers on is likely to overheat the system.

Duplication Controller Solution

While the PC approach offers flexibility and uses familiar components, a system built around a duplication controller offers one major benefit: All the hardware and software needed for the system reside on just one card! With multiple IDE controllers, memory, and firmware dedicated to the task of duplicating CDs and DVDs, all the builder has to do is install a duplication controller card in a case with a suitable power supply and compatible burners. Presto! It's ready to start copying.

With a duplication controller-based system, there is no need for commercial copying software, since all the rudimentary functions like selecting source and targets, copy speed, testing, etc., are programmed into the firmware. Some controller cards support a hard disk for creating and storing disk images, as well as USB ports for connecting to a PC.

For some users, this type of system could represent the ultimate trouble-free solution. It's compact and simple to build, use and maintain. Once set-up, the system is essentially a "one button" operation.

Choosing a Controller Card

To build a duplication tower built around a duplication controller, the first step is to choose a controller. Commonly available duplication controllers can support from as many as nine target burners; some are dedicated CD or DVD burners; and others can copy both CDs and DVDs. There are only a few recognized names in the industry: Wytron and Acard are the best known.

There are only a few choices for duplication controller cards. Acard and Wytron are both respected names. I considered both Acard's DVD-2033 and Wytron's DVD-399, and opted for Wytron's solution after talking to them about compatibility and support. The Wytron DVD-399 controller supports 10 IDE channels and the following media types: DVD-ROM, DVD-video, DVD-R, DVD-RW, DVD+R, DVD+R DL, DVD+RW, DVD-audio, DVD-RAM, CD-R & CD-RW. Wytron has compatibility tested with all the popular burner manufacturers and provide firmware updates. Here's how it looks:

For more complete information on Wytron's line of duplication controllers, contact Orient Instrument Computer Inc. at info@orient-america.com.

Assembly Tips

Systems built around a duplication controller are almost as simple to build as they are to operate. All the parts and assembly recommendations for a duplication controller box are the same as our PC-based solution, except that you'll save the expense and complication of a motherboard, memory, additional IDE controllers, monitor, keyboard and mouse.

As you would with a PC-based solution, carefully plan the location of components in the case. For larger towers--those with more than four burners--locate your duplication controller in a bay half-way down the box to minimize cable clutter and to easily reach all the CD/DVD burners. Also, remember that airflow through the case is critical. Pay special attention to dressing cables so they do not restrict airflow. Also, before doing any significant or prolonged testing, be sure all the sides are back on the case. Testing with an open case can overheat the system.

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Sidebar: Six Tips For Avoiding Disk-Burning Errors

Buffer underrun is the most common problem when creating CDs or DVDs. Underrun occurs when the buffer supplying data to the burner is emptied before all the requested data gets written. The main cause of a buffer underrun is a system interruption. Luckily, such interruptions can be avoided. Whether you're making copies yourself, or training a customer to do so, these six tips and tricks will help keep the copies coming:

• Avoid interruptions. Before you burn any copies, make sure all programs that could interrupt the operation--including screen savers, e-mail clients, anti-virus updates, and fax software--are turned off. If there is a network connection, unplug it, too.

• Keep target files together: If the files you want to burn are scattered across the hard drive, the burning software may have trouble finding them quickly enough to send smoothly to the burner. To prevent this common problem, keep all related files in the same folder. Or, even better, reserve a partition on the hard drive for storing disc images. And, of course, never copy across a network.

• Create a disc image: Most disc-burning software gives you a choice of either creating a disc image of the files to be burned or burning them on-the-fly. An image is simply a single file that contains all the files you want to burn. An image aggregates the data for the burn process and doles it out with the best speed, thus reducing underruns at the burners. One alternative is for the program to pick up files from all over the disk, which involves diffent times to seek and deliver the information that might be interrupted by disk fragmentation or some machine action. Yet another alternative is to copy disc to disc, but this is slow.

• Defrag often: When you save a file to the hard drive, the data is written to blank parts of the disk, which are not necessarily close together or even in the same sector. As a result, a file's data can be fragmented across the disk. Later, when the user tries to copy the file, the software has to find and reassemble all the fragments, and this can slow things down. Defragmentation--better known as defragging--attempts to consolidates each file into a single, contiguous space for fast access. On Windows XP, you'll find the defrag tool by clicking on Start, then Control Panel, then Performance and Maintenance, then "Rearrange items on your hard disk to make programs run faster."

• Burn slower: If you're experiencing trouble, try recording at a slower speed. This will also empty the buffer at a slower rate, and could solve the problem. This is especially important when copying many small files. It's also helpful when copying from a CD-ROM drive that runs slower than the burner drive.

• Test first: While CD-R discs are relatively inexpensive, other media formats, like DVD-RW discs, can be expensive. So before burning, have the software do a test burn. Then, while doing a large run, test occasionally to make sure you're getting good copies. Happy burning!

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ANDY MCDONOUGH is a professional musician, composer, voice actor, engineer, and educator happily freelancing in New Jersey. He enjoys recording and burning perfect copies of his original music CDs and DVDs.