Looking for portable Firewire drives that daisy chain correctly

January 28, 2013 12:33 PM

I'm looking for bus-powered portable Firewire drives that daisy chain correctly. Desired size is 1 terabyte.

By "daisy chain correctly" I mean that I should be able to attach two or three of the drives to my computer in a daisy chain.

I'm asking this question because I made the mistake of buying a pair of Western Digital My Passport Studio drives. After two weeks of fussing I found out that you can't put more than one of these drives in a daisy chain. You can only daisy chain them with different drives. Yeah, right.

Well, that's not what I want. I don't want a bunch of different drives. I want to have two or three, bus-powered, portable, 1 TB Firewire drives, all the same model, that I can daisy chain to my Mac. Reliable, fast, and good looks also desirable.

In case it matters: I'm using a MacBook Air with a Thunderbolt to Firewire adaptor. (As far as I know, USB 3 is not an option. Feel free to let me know if there's an economical Thunderbolt to USB 3 adaptor. That would give me many more drive options.)

posted by alms to computers & internet (6 answers total)

I can't swear that it works correctly, but have you looked at OWC's external drives/enclosures? I've got a couple of their desktop enclosures, which are pretty solid, and if anybody were going to get Firewire chaining right I'd hope it would be them.

You could probably also ask their tech support if their enclosures work properly for FW daisy-chaining.

EDIT: Their ElitePro Mini specifically mentions daisy-chaining FW800 drives.
posted by McCoy Pauley at 12:49 PM on January 28

The problem is not your devices but the Thunderbolt-to-Firewire adapter. In terms of power output, it kinda sucks. Although FW supports up to 45 Watts of 12VDC power for bus-powered drives, the TB-to-FW adapter only puts out about 7W (reportedly). That's not enough to power more than one common 3.5" drive, particularly since Mac OS loves to spin up all its attached HDDs simultaneously (e.g. when you go to "Save" something it will spin up ALL the local disks at once, ugh).

You might have more luck going with two 2.5" drives if they're one of the very most efficient ones available; this will probably involve rolling your own from bare drives and enclosures. (For inspiration: allegedly the MK7559GSXP draws only 2.5W at maximum write, but even with two of them that doesn't leave a lot of overhead for the SATA/FW bridges with only 7W total.) I'm not entirely confident that two would work at spinup, but maybe you could coax them along by plugging one in, letting it spin up and idle, then plugging the other one in. You could probably get two SDDs working though.

I don't think there's much in the way of automatic power negotiation on FireWire so you'd have to experiment a bit, and the quality and length of your cables can affect how well things will work.

But basically, that bridge is designed to run one drive, and that's why you're having issues. It's not the drives; they'd daisy-chain fine (I suspect) on a desktop that supplied the standard ~20W that many implementations provide.
posted by Kadin2048 at 1:18 PM on January 28

McCoy Pauley: The drives I bought are also specifically advertised as supporting daisy chaining. Not mentioned in the product description is that they don't daisy chain with themselves. But I'll still look into OWC.

Kadin2048: That's very interesting and very disappointing! I'll keep it in mind as I shop for new drives. It's not the whole problem though. I was told definitively by Western Digital tech support that you can't daisy chain two WD drives from the same product family.

Anyone have any experience with G Drives?
posted by alms at 1:31 PM on January 28

For the past week I have been daisy chaining identical 1TB LaCie Rugged drives to a MacBook Pro over FireWire800 to copy simultaneous rushes and backups off of SxS cards. They're not pretty or inexpensive, but they daisy chain well and have a USB3 interface for when you don't need to chain them and want slightly faster read/write speeds. I can also vouch for their alleged ruggedness, having seen a few of them get severely mistreated (while spun down/powered off) to the point of having big dents in the aluminum enclosures... they're still working fine.

If the Thunderbolt port is only giving 7W that's probably a show-stopper for daisy chaining any bus-powered drives, though.

(You seem savvy, but I'll mention for the sake of future readers: Even though a drive might have both USB and Firewire connections, one cannot hook up a drive via USB and then chain other drives onto the firewire connections, sorry.)
posted by drumcorpse at 12:47 PM on January 29

Thanks. It looks like the LaCie does what I asked, but not necessarily on my computer due to the low wattage of Apple's Thunderbolt to FireWire adaptor.

Option B might be something like the G-Drive Mini which is described as being bus-powered but also shows a dc power connection. That would let me use bus power when I travel with one drive while also letting me daisy chain drives at home when I can plug in to an outlet for extra power.

Or maybe I'll just stick with the Western Drives and get used to attaching one via Firewire and the other via USB 2. Sigh.
posted by alms at 6:48 PM on January 29

I just got a call from Western Digital. Apparently the knowledge base article I linked to above is out-of-date, and it should be possible to daisy chain the drives. So the culprit is likely the lack of power in the Firewire bus. Next stop: a powered Firewire hub. Fingers crossed.
posted by alms at 12:28 PM on February 11