Overview

Plummeting hard drive prices and the widespread adoption of the SATA interface have combined to create a new type of product, the "drive dock", which connects any number of inexpensive bare hard drives to your Mac as easily as docking an iPod. In comparison to external drive enclosures, these devices have proven to be especially convenient for computer troubleshooting, testing and, perhaps most of all, cost-effective backup, where you pop in high-capacity, high-performance drives instead of slow tapes or optical cartridges.

Newer Technology designed its Voyager Q ("Quad") drive dock, distributed by Other World Computing, to accept laptop (2.5-inch) and desktop (3.5-inch) SATA drives that then connect to your computer via any of its four different storage interfaces: external SATA (eSATA), FireWire 800, FireWire 400 and USB 2.0.

Externally, the Voyager looks like a sci-fi toaster, complete with lever-tab on the front and a big slot on top. But instead of a slice of bread, you pop in a bare hard drive. A spring-loaded panel on top, with a cutout, helps you line up a laptop drive, or folds down out of the way when you insert a desktop drive. A circular blue light on the front panel indicates power, blinking red during disk activity. The base is weighted and has rubber feet to keep from sliding around a desk. Overall, the Voyager seems quite robust.

Connect your choice of cable to the back (one of each type is included in the box), then turn on the Voyager by pressing the power button below the eject button. USB and FireWire support hot swapping — unmount the drive from the Mac's desktop, power off the dock, then press the front lever to pop the drive up, and pop in another drive.

The Voyager must be turned off before switching between interfaces. It appears to activate the first port you connect after it turns on, ignoring the others.

Using eSATA may require rebooting your Mac to mount and unmount drives, although some eSATA cards and drivers may support hot-swapping.

The Voyager's eSATA bridge looks to a Mac Pro like any other SATA device, but adds "eSATA-2" to the drive's model identifier. In System Profiler, our test drive was transformed from model "ST3400620AS" to "eSATA-2 ST3400620AS". We also noticed that the Voyager does not support NCQ (native command queueing), a performance-enhancing but optional SATA feature.

Otherworld Computing tell us the Voyager's bridge chipset been tested with volumes up to 8 terabytes. The SATA spec includes 48-bit LBA drive mode, supporting volumes up to 144 petabytes (over 150 million gigabytes). The Voyager should support growing drive capacities for quite some time.

Performance

SATA is the fastest of the quad interfaces, followed by FireWire 800, then FireWire 400, with USB 2.0 bringing up the rear. (Other World Computing also offers the Voyager S2, a non-FireWire version at half the price without any FireWire support.) To find out how the various interface options compare, we tested a 400-GB Seagate 7200.10 drive in the following configurations, using a 2.66-GHz Mac Pro system:

* SATA (Mac Pro internal bay 2);
* Voyager Q eSATA;
* Voyager Q FireWire 800;
* Voyager Q FireWire 400;
* Voyager Q USB 2.0; and
* Thermaltake BlacX USB 2.0 (a popular, non-FireWire dock).

We measured raw throughput using AJA Kona System Test and ran Intech's QuickBench to get an idea of where the FireFire and USB bridges are strongest.

(External SATA testing was done with a Newer Technology eSATA Extender kit for Mac Pro. This kit provides two external SATA ports by connecting to two unused SATA ports on the Mac Pro logic board.)

AJA System Test

AJA System test is one of our standard benchmarks, created to measure drive throughput for video applications. We run AJA's "Sweep File Size" option, which writes and reads data in a series of blocksizes, selecting the Disable File Cache option. The graph below shows read and write performance for large blocks (i.e. top sustained transfer rates).

Here, we see that FireWire 800 is twice as fast as USB 2.0 or FireWire 400, but about 20% slower than SATA. We note that FireWire 400 was only marginally faster than USB 2.0 — this was not our experience with earlier Mac models, where FireWire 400 routinely outpaced USB 2.0.

Although the Seagate drive actually writes a bit faster than it reads in this test case, as shown in the SATA scores, writes are slower than reads for FireWire and USB with either dock. We've seen similar behavior in many other drive enclosures and adapters, perhaps due to the "bridge" electronics that support USB and FireWire.

QuickBench

Intech's QuickBench 4.0 provides a good read on a disk system's overall performance. Quickbench performs sequential and random reads and writes across a range of file sizes from 4 KB (the length of a typical email message) to 1 MB. QuickBench performs five runs, drops the slowest, and averages the remaining 144 distinct runs to present final numbers, which we charted with Numbers '09.

Here, we present both the performance charts and the top speed for each configuration.

At small sizes, traditional spinning platter hard drives are typically very inefficient and slow; they hit their stride in larger transfers where they spend less time seeking.

Comparing the internal SATA to eSATA charts, we see there is a slight performance penalty from the Voyager's SATA bridge across most of the range — except right at the top end, where write speed picked up. But read speeds were consistently about 4 MB/sec lower on eSATA. Still, even the slightly degraded eSATA speed is much faster than FireWire.

The Voyager Q's FireWire bridge seems to achieve its best speed with file transfers around 512 kb. USB 2.0 hits its limit 128 kb chunks — probably an artifact of the USB protocol's small frame sizes. (This is a long-standing problem in the USB specification, which keeps it from attaining anywhere near its theoretical 480 Mbit/sec rating.)

Conclusions

Who needs a drive dock? We see several scenarios. For one, anyone regularly working with huge project files, and multiple drives can save money and time with a dock (video producers, we're looking at you!). It's also a great tool for tech support; it makes imaging drives or recovering data faster and easier. Every help desk needs one, and the Voyager (or something like it) should be in the toolkit of independent Mac consultants.

As we mentioned at the start of this review, drive docks have clear value in backup applications. Best practices are to rotate multiple storage containers, so that a single failure doesn't wipe out all of your backups. Ideally, you'll have at least one offsite backup at any time. A drive dock makes this very easy to manage.

The Voyager Q's $99 price tag is justified by its quad interfaces, which maximize throughput across every different Mac, whichever you happen to be using at the moment. FireWire 800-equipped Macs — such as the PowerBook G4, MacBook Pro and new Mini — get double the performance vs. USB 2. Older Macs, such as the Pismo PowerBook G3 and graphite iMac, get maximum performance via FireWire 400 (far, far faster than USB 1). Power Macs, Mac Pros and MacBook Pros can add an eSATA card, if they haven't already, and get performance comparable to high-performance, internal desktop hard drives. Whether you're compiling software, editing video or doing large backups, this can save a lot of time. The extra $50 over the USB-only model is well worth it if you regularly push a lot of data.

We've used the BlacX USB dock for some time, and it's hugely useful already, so we weren't expecting to be impressed by the Voyager. But the speed difference between the USB-only BlackX and the Voyager Q's FireWire 800 is night and day — not to mention the Voyager's superior construction. We like it. If speed's your need, combined with convenience, the Voyager Q may suit you, too.

Pros

* quad interface maximizes performance for any Mac
* sturdy construction with weighted base

Cons

* more expensive than USB-only docks