Promise Pegasus Portable Thunderbolt Drives Now Available!

Promise Pegasus Portable Thunderbolt Drives Now Available!

It was quite a while ago that I did a piece on hard drives -- the inevitable non-photo, but techy part of every photographer's gear. It's been a while, but manufacturers have been hard at work, including Promise with their Pegasus J2 and J4 Thunderbolt drives. Today, after having been announced back in May, they're finally available to order!

When we're editing our photos, one of the things that slows us down the most are our hard drives. If you're not using solid state, you'll notice this even more as previews and full resolution images take forever to load -- especially with today's 36+ megapixel cameras. And if you wanted true solid state speed, your only option was to throw one into your laptop (or desktop) for several times the cost of your standard hard drive, despite the drive having less space.

Now, thanks to Thunderbolt, we can see SSD speeds in an external device -- one that's portable, no less. Other hard drives have come out with Thunderbolt support before, but the J2 and J4 enclosures/drives offer more versatility.

While the J2 is a small, two-drive RAID configuration that comes in 256GB or 512GB capacities, the J4 will be available as the 4-bay enclosure alone for a cool $399, as opposed to the $799 and $1499 price tags of the J2 configurations. And while it holds four 2.5-inch drives (spinning or solid state), it's just the size of a Mac Mini.

The J2 features read and write speeds of 750MB/s and 550MB/s respectively that drop to a still-amazing 500MB/s read and write when bus powered (when they take their power from the Thunderbolt port as opposed to the wall). The J4, on the other hand, features almost the same speeds at 700MB/s/500MB/s read/write. With standard hard drives, the J4 can still perform at 400MB/s/300MB/s read/write -- and none of that is anything short of amazing.

For now, the J2 is the only drive shipping. But the J4 is likely around the corner, now that we have specs and pricing.

You can order the J2 from B&H here or on Amazon here.

When are you ordering yours?


Oddly enough, Apple's website says that the J2 can only support 110MB/s and 270MB/s write and read speeds on bus power, while the PDF in the email I received from Promise this morning said otherwise:

From Apple's site.

From the email I received from Promise this morning.

Also, here's a bit more info on the J4 from that same PDF as well as the R6 desktop RAID system also explained in the document:

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Mike Folden's picture

Have you guys tried out the Seagate GoFlex with the TB adaptor? SSD's are rad but I go through 1TB every few months for video and the price above just doesn't work with me. I'd love a review on the Seagates though!

Adam's picture

My current MacBook Pro doesn't support Thunderbolt, but it's time for an upgrade soon, at which time you can be sure I'll be testing some of these.

That said, I'd never use these drives for straight-up storage. I go through data quickly, too, but these would be great for portable work drives that you can have live work on until you can move the finished product to a backup/storage drive when it's all said and done... Getting one of these could make editing large/complex files bearable on a machine with 'normal' hard drives.

hopefully in like 4-5 years SSDs will be "norm" and spinning drives out. This way I guess price will fall and their capacity will increase? Spending "few" $100 on 256GB is a bit too much at the moment for most of us :(

There's also this el gato 240Gb SSD for 200 less than the promises J2.

Adam's picture

yes, and I'm sure it's great. However, to note, the J2 offers quite a bit more speed...if you need it...

Adam, thank you so much for sharing that! I've been waiting for more information on the Promise Pegasus J4.

Do you have any idea whether tall 2.5 inch drives will be supported in the empty Promise Pegasus J4 enclosure?

I'd love to buy one to put four WD Green Mobile Hard Drives: because of their unusually high capacity (up to 2 TB for 2.5 inch hard drives); but that's only possible because they're 15mm tall instead of the more typical 9.5mm.

Adam's picture

I'm not sure at the moment. I'm trying to get more information on that in the coming days. Part of me wants to think it must (the size doesn't seem too restricted...i.e. they should have been able to make 15mm drives work), but we'll see... I'll update as I know more. But yes, that would be fantastic. Some similar systems exist (like Drobo's), but they don't allow bus-powered operation like the J4 does -- that's what I'm really excited about. And honestly, who cares if it 'only' does 500MB/s...that's still MORE than enough for any photo editing needs...