Outside Storage

It wasn't so long ago that I was considered a freak for making a notebook computer the center of my studio. Compared to the awe-inspiring Pentium 60 desktops

It wasn't so long ago that I was considered a freak for making a notebook computer the center of my studio. Compared to the awe-inspiring Pentium 60 desktops of the day, notebooks were slow and limited. Audio hardware for laptops came in two types: vaporware and buyer-beware. Worst of all, recording to a 400 MB hard drive gave new meaning to the term “cramped quarters.”

Now that using notebooks for audio production is commonplace, all those problems have been resolved, right? Not exactly. There are indeed a number of appealing audio interfaces on the market, and notebook processors have advanced to the point of being more than adequate for almost any audio task. Storage, however, is a different issue.

With very few exceptions, notebooks are equipped with only one hard drive. That simple fact is bad news for laptop audio engineers for three reasons. First, using a dedicated audio drive that is separate from the system drive is a simple and cost-effective way to get more tracks out of your computer. That's because the drive reading and writing audio data is unimpeded by requests to deliver OS or program files. Second, a single drive gets cluttered and cramped too quickly, especially when a typical 20 GB notebook drive shares its space with the operating system, programs, libraries of samples and loops, and so forth. The third reason has to do with drive speed: most laptop drives spin at a measly 4,200 rpm, barely more than half the speed of a typical 7,200 rpm desktop drive. (For reliable audio performance, 7,200 rpm is the minimum acceptable speed.)


As you can see, it's best to have a dedicated audio drive for your notebook — one that's big enough and fast enough to hold your dream sessions. Because there's no room inside your notebook to install such a drive, your only option is to connect an external drive. There are a few different ways to accomplish that, but let's start with the one that's capturing all the attention of late: FireWire.

Properly known as IEEE 1394, FireWire combines a data pathway capable of moving 50 MB per second (400 Mbps) with Plug-and-Play connectivity and hot-swappability. Theoretically, you can daisy-chain a large number of devices on a single FireWire port, but because they all share the same bandwidth, there's a practical limit to how many devices you would want to chain.

For a notebook equipped with at least one IEEE 1394 port, attaching an external FireWire drive (see Fig. 1) and hitting the Record button is about all there is to it. Most current FireWire drives use 7,200 rpm IDE drives, offering plenty of speed at a reasonable price.

One thing to watch out for is that not all IEEE 1394 connections are created equal. It's less of an issue with more recent devices, but early implementations of the protocol often operated at less than the full bandwidth. For example, according to Jim Cooper of MOTU, “Older iMacs and Blue G3s were equipped with 200 Mbps [FireWire] buses, as are several PCI and CardBus [FireWire interfaces]. Buyers should always check to make sure that any FireWire expansion products they are thinking about purchasing offer 400 Mbps bandwidth.”

MOTU's 896 FireWire audio interfaces feature pass-through ports that allow users to chain multiple interfaces and FireWire hard drives, and MOTU's 828s can be chained to drives that have a pass-through port (or you can use a powered hub). “Our experience is that one FireWire hard drive, in terms of bandwidth, equals one 828. So you could have three 828s and one FireWire drive, for example,” according to Cooper. When using the 896's higher sampling rates, of course, track count is cut by about half.

Gordon Lyon, Digidesign's Product Manager for Storage and Compatibility, states that good indicators of a FireWire drive's suitability for audio include 7,200 rpm rotation speed, 100 MHz ATA bus, and the Oxford 911 chip. Not surprisingly, one drive matching that description is Digidesign's own DigiDrive FireWire 80, which is capable of being daisy-chained to a Digi 002 FireWire interface without compromising performance. Oxford Semiconductor's 911 chip seems to be a common denominator for many of the FireWire drives being sold for DAW use. (The truly power-mad will no doubt be excited to know that Oxford has announced the 922 chip, supporting the next generation of double-speed FireWire devices.)

Operating-system support for FireWire drives is respectable on both Macs and PCs, but the vendors with whom I spoke generally recommended using the latest versions of the operating systems. As always, it's a good idea to check your DAW manufacturer's online tech notes or compatibility documents before parting with your hard-earned cash. Notebooks with 4-pin FireWire connections will need an adapter cable to connect to a drive, which uses a 6-pin connection.

How fast is fast? The bottom line, of course, is how many tracks you can expect to record and play back with a FireWire hard drive. As with most computer-performance questions, the answer is, “It depends.” There are so many variables involved that hard numbers are hard to come by. Processor speed, driver design, choice of software, bit depth, sampling rate, background applications, and other factors all have to be taken into account.

The good news is that the numbers I've heard are all pretty encouraging. I've heard numerous reports from users of getting 64 or more tracks of 24-bit, 44.1 kHz audio playback from a single FireWire drive attached to a reasonably powerful notebook computer. The most conservative numbers come from Digidesign, whose systems support up to 24 tracks of 24-bit, 48 kHz audio per FireWire drive.

Glyph Technologies conservatively rates its 80 GB Companion FireWire drive for 48 tracks of playback with no edits or 48 tracks of recording at 24-bit, 48 kHz resolution. At 96 kHz, those numbers drop to 40 tracks, but with two edits per second across all tracks the numbers drop by about half. That's not unique to FireWire drives, but because they spin at 7,200 rpm they are more sensitive to edit density than are the 10,000 rpm drives typically used in SCSI configurations. (According to Glyph, these results are based on Digidesign's own torture test, which stresses the drives far beyond typical recording, mixing, and editing use.)

The most optimistic numbers I've seen claim 120 tracks of 24-bit, 44.1 kHz audio with an edit density of two edits per second. At a 192 kHz sampling rate, the highest numbers are 24 tracks for a single drive. For the most up-to-date information, be sure to check the vendors' Web sites (see the sidebar “Checking the Specs”). As they say, your mileage may vary.

While most FireWire drive vendors are touting their well-insulated noise-suppressed external drives, a company called WiebeTech is taking the opposite approach with its DriveDock line of FireWire bridge modules (see Fig. 2). The DriveDock attaches on one side to an IEEE 1394 cable and on the other side to a naked 3.5-inch hard drive (or CD or DVD drive). What this setup lacks in sex appeal and noise-proofing it makes up for in convenience, price, and flexibility. You could literally have a single DriveDock and a bag full of hard drives and swap out the drives from project to project. The DriveDock requires an AC adapter, but its sibling the Super DriveDock is bus powered.


USB 1.1 drives have quite appropriately been dismissed as inadequate for digital-audio recording. With a maximum data rate of 12 Mbps (compared to IEEE 1394's 400 Mbps), USB could under ideal circumstances deliver a few tracks of 24-bit, 44.1 recording or playback. Most modern notebooks would do much better using their internal drives.

USB 2.0 increases the stakes to 480 Mbps (maximum burst rate), surpassing (in theory) the performance of current FireWire devices. (USB was not designed to handle large blocks of streaming data, such as digital audio, as efficiently as FireWire does, so it demands more processing overhead for any given audio command.) While some manufacturers are taking a wait-and-see attitude, Cakewalk's Vice President of Engineering Ron Kuper says, “I think USB 2.0 has a strong future for audio.” With USB being ubiquitous on Macs and PCs and FireWire still optional on PCs, there has been a lot more development in audio devices for USB than for FireWire. Although Apple is bullish on FireWire, “Intel and Microsoft are strongly behind USB 2.0, and USB is cheaper, so the average PC user is way more likely to see an integrated USB solution on their motherboard,” says Kuper.

Microsoft has delivered native USB 2.0 support in its first Service Pack to Windows XP. (Unlike FireWire, USB 2.0 wasn't ready when XP was first released.) Eighty percent of PCs shipped in 2003 are expected to have integrated USB 2.0 support. (Meanwhile, Apple says it is “watching” USB 2.0.) Numerous USB 2.0 CD-R and hard-drive products are already available, but none of the audio-centric drive vendors has taken the plunge yet. A number of the USB 2.0 drives that are currently available feature dual support for either USB 2.0 or FireWire, raising some enticing possibilities. Track count for USB 2.0 drives could be as good as FireWire drives as long as the device has a 7,200 rpm rotation speed.

Another interesting development in USB storage is the appearance of several models of key-chain USB devices such as the ThumbDrive from Trek (see Fig. 3). These solid-state storage devices come in sizes from 16 MB all the way up to 1 GB. Although they're not fast enough to record and play back multitrack audio, they are a convenient way to carry around lots of small- to medium-size files that might come in handy. You could keep favorite loops or drum replacement samples, test tones, plug-in presets, song ideas, or anything else to which transfer speed isn't critical.


The best performance in notebook hard drives is still found in SCSI devices. CardBus-to-SCSI adapters open the world of SCSI performance to the mobile engineer, but in general the cost is higher than with FireWire. That's partly due to the fact that FireWire ports are built in to many notebooks, whereas built-in SCSI ports are quite rare. Therefore, for starters you would have to purchase the adapter. The rest of the story is that the cost of SCSI hard drives is higher than that of ATA drives, so you get hit coming and going. Still, if performance is your top priority, SCSI is the way to go. Another option to consider is that Magma's CardBus-to-PCI expansion chassis is available with SCSI support built in.

The storage options for notebook-lugging musicians have never been better. You can have any or all of the things you desire in external storage: convenience, affordability, speed, noise-suppression, capacity, and compatibility. I still wouldn't turn up my nose at a hot-swappable SCSI-160 drive bay in my next notebook, but at least now I don't have to hold my breath.

Brian Smithersis working on retrofitting his calendar with support for FireWire drives to increase its storage capacity. In his spare time he teaches at Full Sail Real World Education in Winter Park, Florida.


For current specs and up-to-date information on external drives, check out the vendors' Web sites.

AVammo, Inc.
compact FireWire drives

Digidesign, Inc.
DigiDrive FireWire 80; Digidesign's compatibility documents, though intended for Pro Tools systems, are a useful reference for anyone designing a DAW system

Glyph Technologies, Inc.
FireWire and SCSI external drives

PCI expansion chassis

Pacific Pro Audio
fast and quiet FireWire drives (among other things)

Trek 2000 International Ltd.
Trek's tiny little storage devices

DriveDock FireWire adapters