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LaCie 2big Thunderbolt review: LaCie 2big Thunderbolt

LaCie 2big Thunderbolt

Dong Ngo
Dong Ngo SF Labs Manager, Editor / Reviews
CNET editor Dong Ngo has been involved with technology since 2000, starting with testing gadgets and writing code for CNET Labs' benchmarks. He now manages CNET San Francisco Labs, reviews 3D printers, networking/storage devices, and also writes about other topics from online security to new gadgets and how technology impacts the life of people around the world.
8 min read


LaCie 2big Thunderbolt

The Good

The easy-to-use, high-capacity <b>LaCie 2big Thunderbolt Series</b> offers very fast performance for a dual-bay external hard drive. The drive supports RAID configurations, has a user-serviceable hard-drive bay design, and can be daisy-chained with up to five other Thunderbolt devices without decreasing the throughput.

The Bad

The LaCie 2big Thunderbolt's performance is comparatively slow for a Thunderbolt storage device, especially in RAID 1. The drive is relatively expensive; it doesn't have built-in support for any other common peripheral connections like USB or FireWire; and it doesn't come with the necessary Thunderbolt cable.

The Bottom Line

The LaCie 2big Thunderbolt Series strikes a balance between capacity, performance, and price and would be a good choice for owners of Thunderbolt-enabled computers.

The LaCie 2big Thunderbolt Series is like the other hard drives in the 2big family, such as the 2big USB 3.0, with just one difference: it uses the new Thunderbolt connection and no other connection types, meaning it forgoes USB, FireWire, and eSATA. And this is a big difference.

This is the fastest dual-bay external hard drive I've seen, even though it's noticeably slower than other Thunderbolt devices, such as the LaCie Little Big Disk SSD and the Promise Pegasus R6. To make up for not being the fastest, the 2big Thunderbolt Series, though in no way cheap, costs significantly less than its competitors at $650 for the 4TB version and $800 for the 6TB. (Like with other Thunderbolt drives, you'll have to spend another $50 for a Thunderbolt cable, which is not included.)

That said, the LaCie 2big Thunderbolt is a good choice if you need a storage product that supports Thunderbolt and don't want to spend too much on something that's overkill for your needs.

Drive type External Thunderbolt hard drive
Connector options Thunderbolt
Available capacities 4TB, 6TB
Product dimensions (LWH) 3.7x7.9x7.2 inches
Weight 7.9 lbs
Capacity of test unit 6TB
OSes supported Mac OS X 10.6.8 or later.
Software included Intego BackUp Manager Pro

Design and features
From the front, the LaCie 2big Thunderbolt looks exactly the same as the 2big USB 3.0, with a large blue circle that glows to show that the device is powered and ready. On the back the drive has two hard-drive bays that can each hold a 3.5-inch SATA hard drive of up to 3TB, for a total top capacity of 6TB when the drive is set up in RAID 0. In RAID 1, this total usable capacity is reduced by half, with the other half being used as redundancy in case of hard-drive failure.

Each drive tray is locked in place via a latch that can be opened with a coin. In case you don't have a coin ready, LaCie also includes a little plastic key for the job. Once open, the drives can slide out relatively easily. After that, you'll need a Phillips screwdriver to replace the hard drive. Note, however, that if you choose to replace the hard drive, the warranty will be voided. Another note is, while LaCie says the hard drives are hot-swappable, you should only do that when they are set up in RAID 1. In RAID 0, which is the default setup, pulling out a hard drive when the drive is in operation will damage the data.

Also on the back, you'll find two Thunderbolt ports. This means when used in a daisy-chain setup, the 2big Thunderbolt can be any part of the chain. I tried it with a few other Thunderbolt devices, including the Pegasus R6 and the Apple Thunderbolt Display, and the chain worked out very well, with no sign of bandwidth reduction.

The 2big Thunderbolt has no power switch, so you can't turn it on and off while it's plugged in. However, this is no big deal since the drive's power status works in sync with that of the host computer. You can't turn it on without first connecting it to a Thunderbolt-enabled computer. Once plugged in, the drive turns itself off when the computer is off or in sleep mode, and goes back on when the computer is in operation. In my trials, the drive remained on when the computer went into sleep mode, however.

The drive comes with a detachable base to hold it in a vertical position. It can work on its side as well, but I see no reason not to use the base.

Out of the box, the 2big Thunderbolt comes with more than you need in terms of power plugs. The drive's two-part power adapter comes with enough power heads to fit in any type of receptacle around the world. Since this is a desktop external storage device, which would generally be used in one place, this is likely a waste. It would be much better if you could swap all the extra power heads for the necessary Thunderbolt cable, which is not included and costs another $50.

There's nothing to setting up the LaCie 2big Thunderbolt. Out of the box, it's preformatted in HFS+, and once connected to a Mac via Thunderbolt, it's immediately available to the computer, just like other external storage devices. If you want to use the drive in RAID 1, however, you'll need to run Disk Utility to change the RAID, which took less than a minute in my trial.

The drive comes with a CD that contains Intego Backup Manager Pro software. Since the drive is easy to set up and it's probably best to use it with your Mac's Time Machine for backing-up purposes, it's likely you won't need to use this CD at all.

The LaCie 2big Thunderbolt Series is the first dual-bay Thunderbolt-based storage device I've reviewed. This means it's only similar to the Pegasus R6 when set up in RAID 0. In RAID 1, it's very much like a single-volume external hard drive. This is because in RAID 1 the bandwidth of the drive is limited by that of the internal hard drive. The reviewed unit comes with two 3TB Seagate Barracuda hard drives that spin at 7,200rpm. The hard drives support SATA 3, which caps at 6Gbps, much slower than the Thunderbolt standard's 10Gbps. In my tests, there was a big difference in the 2big's performance between the two RAID setups.

I put the LaCie 2big Thunderbolt through two sets of performance tests. In the first set, I compared it with internal drives, both traditional hard drives and solid-state drives (SSDs). In the second set, the drive was stacked up against other popular external devices that use USB 3.0, USB 2.0, FireWire, and eSATA connections.

The test machine is a 2011 MacBook Pro running OS X Lion, with a SATA 3 (6Gbps) SSD. Again, note that, though among the fastest on the market, the notebook's internal drive has a significantly slower ceiling speed than the 10Gbps (about 1.2GBps) of Thunderbolt.

For the first set of tests, I used the Pegasus R6 connected to the LaCie and benchmarked how fast the LaCie transferred data to and from the Thunderbolt partner. After that, I took the R6 out of the chain and tested the 2big on its own. The host computer's internal storage doesn't have much effect on this set of tests.

In RAID 0, the 2big performed well when working with the R6, registering write speeds of about 240MBps, faster than any other dual-bay external hard drive. It was slower than the Pegasus R6, however, which scored 353MBps in the same test. When working alone and performing both read and write, the 2big averaged 111MBps, again much slower than the R6, but still faster than some SSDs.

The same tests were repeated with the 2big's hard drive being set up in RAID 1. This time around the drive performed much slower, close to a regular internal hard drive, registering 130MBps and just 60MBps, when working with the R6 and alone, respectively.

In the second set of tests, I basically tried using the LaCie 2big Thunderbolt the way most of us would use an external hard drive: copying data back and forth between it and the host computer's internal drive. In this test, the LaCie scored 179MBps for writing and 181MBps for reading in RAID 0. In RAID 1, it was slightly slower at 127MBps and 147Mbps, for writing and reading respectively. These numbers were slower than those of the R6 (RAID 5) but it still performed faster than any non-Thunderbolt external storage devices.

All in all, the LaCie 2big Thunderbolt performed as I expected, with RAID 0 showing much better performance than RAID 1. In either case, it was still one of the fastest external storage devices on the market. That said, if you intend to use it to host important data, make sure to change its hard-drive configuration to RAID 1 to keep your data safe.

The LaCie 2big Thunderbolt worked well in my trials even after long and heavy operation. The drive emitted almost no noise at all. Its blue round light, however, could be a nuisance if you want to keep the room dark.

Data transfer speeds Thunderbolt vs. internal drive (in MBps)
(Longer bars indicate better performance)
Unit to unit  
Self read and write  
Promise Pegasus R6 (RAID 0)
Promise Pegasus R6 (RAID 5)
Plextor PX-256M2S
OCZ Vertex 3
LaCie Little Big Disk SSD
Crucial M4
LaCie 2Big Thunderbolt (RAID 0)
OCZ Agility 3
Patriot Wildfire
LaCie 2Big Thunderbolt (RAID 1)
WD VelociRaptor 600GB
Seagate Barracuda XT
WD VelociRaptor 300GB

Data transfer speeds Thunderbolt vs. external drive (in MBps)
(Longer bars indicate better performance)
LaCie Little Big Disk SSD
LaCie 2Big Thunderbolt (RAID 0)
LaCie 2Big Thunderbolt (RAID 1)

Service and support
LaCie backs the 2big Thunderbolt Series with a three-year warranty, which is good compared with the Pegasus R6's two-year warranty. At LaCie's Web site, you have access to the device's documentation, knowledge base, and FAQs, and can download software to use with the device. If you want to contact LaCie, you'll first have to register an account with the company, however, which can be a hassle when you need help immediately.

The LaCie 2big Thunderbolt series, though very fast, is the slowest of the few Thunderbolt-based storage devices on the market. It more than makes up for this, however, by being much cheaper than the other Thunderbolt storage devices in terms of cost per gigabyte. In short, the drive offers a better balance of cost, capacity, and performance and I'd recommend it to any owner of a Thunderbolt-enabled Mac who needs a superfast external storage device.


LaCie 2big Thunderbolt

Score Breakdown

Design 8Features 6Performance 8Support 6
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