The product in question is the Echo Thunderbolt to ExpressCard/34 adapter from Sonnet, which allows you to plug in ExpressCard/34 accessories and then use them via your Mac’s Thunderbolt port. ExpressCard/34 is a connection standard that’s only available built-in on 17-inch MacBook Pros, and allows you to plug in various adapters, like USB or FireWire hubs, memory card readers, modems, eSATA and USB 3.0 port add-ons.

So far, we’ve yet to see too many Thunderbolt accessories go into production, or at least ones that cost less than $1,000. There’s the Pegasus RAID array available through the Apple online store, which is admittedly a good deal for that kind of hardware, but it’s a little pricey for ordinary users. And Apple also recently introduced Thunderbolt Cinema Displays, but that’s also something that might appeal more to professional customers.

With the Echo ExpressCard/34 adapter, anyone will be able to use drives that support USB 3.0 or SATA high-speed transfer technology with their Macs, as well as add FireWire, Ethernet or memory card reader ports to computers that don’t have them, like the MacBook Air. The adapter will admittedly be a bit bulky, and its $150 cost is just the starting point, since you’ll have to buy the appropriate ExpressCard/34 adapter as well as any drives or accessories you want to use with your Mac, but it still puts things in a much more affordable range than the current crop of available Thunderbolt-powered add-ons.

The Echo is available for pre-order, and ships in October. It’s definitely one way to make your computer’s Thunderbolt more useful, but would you rather wait until more direct solutions appear? Let us know in the comments.

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However, as I learn more about the Secure Digital format, both what’s already available and what’s coming, I’m even more convinced that Apple made the right call.

For one thing, while ExpressCard 34 cards are smaller than the old PCMCIA CardBus cards they replaced, the standard SD Card format measures 32mm x 24mm in footprint (roughly the viewing area of a 35mm film negative or slide) vs. 75mm x 34mm for the ExpressCard, and it is only 2.1mm thick. That is especially helpful in computers as thin as Apple’s MacBook family — even more so if Apple builds a tablet or notebook smaller than the MacBook Air.

Another SD Card advantage is hardware standardization. The SD format shows potential for becoming the standard for removable storage in portable computers. The majority of PC laptops, and most netbooks, are available with SD Card slots, so Apple is no longer the odd man out in that context. Apple portables honcho Todd Benjamin told PCMag’s Mark Hachman in an interview that one reason the company went SD is that the format has become “really ubiquitous,” and not just in laptops. Consistent with Apple’s focus on consumer electronics and Mac market positioning as a digital hub, SD Card support is built into a myriad of consumer digital devices, especially cameras and Mobile Internet Devices (MIDs).

The iPhone doesn’t support removable storage as of yet, but in my opinion, it’s virtually inevitable that it will, and when it’s added, the tiny Mini SD variant (15mm x 11mm) is a likely bet.

SD Cards Just Have More to Offer

Currently, standard SD Card storage capacity tops out at a modest 4GB, but a much higher capacity variant, called SDHC, offers up to 32GB, and an eXtended Capacity SDXC spec that was unveiled at this year’s Consumer Electronics Show supports memory capacities above 32GB up to a potential 2TB, with data transfer speeds up to 104MB/sec and potential future throughput up to 300 MB/sec. The SDXC standard uses Microsoft’s exFAT file system (FAT64). Existing SD and SDHC host devices won’t be compatible with the new SDXC cards, but SDXC host devices will be backwards-compatible to work with SD and SDHC cards. A microSDXC card also is reportedly in the works for use in small mobile devices, with plenty of development headroom apparent in the SD format.

Cards conforming to SD (4MB to 4GB) and SDHC (4GB to 32GB) standards are supported by the slots in the new MacBook Pros. MultiMediaCards (MMC) can also be used in this slot, while MiniSD, MicroSD, and higher density formats like MiniSDHC and MicroSDHC can work but require “passive” adapters that conform to the standard SD width and thickness specifications.

MacBook Pro SD Card slots support a maximum throughput of 240Mbit/s, which exceeds the transfer rate of most SD media (about 17-21Mbit/s to 30Mbit/s, depending on type) by a substantial margin. MacBook Pros recognize cards inserted in their SD card slots as USB storage devices that can be mounted, read from, and written to as with any other USB storage device.

You can even make SD Cards (with a capacity of at least 8GB) bootable by changing their default partition table to GUID using Mac OS X Disk Utility and formatting the card to use the Mac OS Extended file format, instead of standard FAT32 DOS formatting. Macworld’s Roman Loyola has posted a video tutorial showing how to create a bootable SD Card. Loyola also reports that a variety of other Macs, besides the SD Card equipped mid-2009 MacBook Pros, including an iMac and a Mac mini, can be successfully booted from SD Card boot disks via a SanDisk MicroMate SD card reader.

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Does this move represent wise decision-making, or is it a blunder on the scale of the misbegotten elimination (now thankfully rectified) of FireWire support from the first revision 13″ unibody MacBooks? I think the ExpressCard/SD Card tradeoff makes some pragmatic sense. It would be great to have both formats, but for most users, SD Card support will be more functionally useful. Apple CFO Phil Schiller was quoted on Monday saying that surveys had determined only 10 percent of MBP owners ever used the ExpressCard slot.

As much as I like the idea of having ExpressCard capability in my laptop, I’m doubtful that I would miss having it on any machine that has built-in FireWire. I did make a fair bit of use of the PC CardBus slots in my G3 PowerBooks back in the day, and still do use the one in my “road” Pismo for a Buffalo G54 802.11g adapter card I use in conjunction with OS X’s AirPort software to log onto Wi-Fi hotspots. However, built-in AirPort has been standard on even the cheapest Apple notebooks for about five years now. On the other hand, an SD Card slot would be very useful for transferring image files from my digital camera. (Alas, my 13″ unibody MacBook has no slots and no FireWire.)

However, there are a minority of users who depend on the ExpressCard slot — for example, 3G cards for Wi-Fi connectivity, Gigabit Ethernet cards to provide a second network connection, or cards to provide extra FireWire ports on their own dedicated bus operating at full speed instead of daisy chaining devices. There are also ExpressCard-based PCI expansion options used by audio and video pros, and they work with ExpressCard interfaces. ExpressCard-based eSATA interfaces are also available for data transfer faster than FireWire 800 can support, and some folks, of course, use ExpressCard-SD card adapters or a variety of other media card readers such as 7-in-1 readers or 12-in-1 readers that can read much more than just SD cards. With an SD Card slot, you can only read one type of card.

All that said, Apple’s director of portables, Todd Benjamin, told PCMag’s Mark Hachman in an interview this week that the ExpressCard 34 slot was dropped from the 15″ MacBook Pro because the “vast majority” of owners use USB connectivity, and that Apple opted for a SD Card slot because that format has become “ubiquitous.”

The obvious solution, if one absolutely requires ExpressCard support, is to get a 17″ MacBook Pro, which at least is now more reasonably priced at $2,499, and most professional notebook users should find that affordable. The 17-incher is a bit larger and heavier to lug around, but having the bigger display is no hardship, and as a 17″ PowerBook owner myself, I would say that the diminished portability aspect is often exaggerated. I’ve found mine a surprisingly tractable road warrior-ing machine.

So, which would you prefer: ExpressCard 34 or SD Media Reader?

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Transcend Solid State Device

Without any doubt, this is the ExpressCard device which caught my eye first. It consists of a high capacity, solid state device which inserts into your laptop, giving you an easy way to add some SSD storage. Initially the price of these was prohibitively high, but SSD is becoming evermore appealing as the costs are pushed lower. It comes in three different varieties:

• 32GB SSD $126.21
• 16GB SSD $44.68
• 8GB SSD $28.68

The major use heralded for the card is to enable Vista ReadyBoost — something obviously not appropriate for a MacBook Pro user. However, other tasks which benefit from high speed storage (a Photoshop scratch disk for instance) could see the benefit of the card. Whether it provides a huge advantage over a high capacity USB thumb drive is debatable though, and the ExpressCard price still carries a slight premium.

Macally 5-in-1 ExpressCard Media Reader

Something I was always used to on a Windows desktop was a media card reader. After having a MacBook for a few years, I’ve now become accustomed to just plugging a camera in via USB. That said, I would certainly find an ExpressCard memory card reader particularly useful.

A few readers have received fairly poor reviews, but the Macally offering seems better than most. It is able to convert ExpressCard to Memory Stick, Memory Stick PRO, Secure Digital card, MultiMedia card and xD-Picture Card. It does have some limits on capacity, however:

• Memory Stick – up to 128MB
• Memory Stick PRO – up to 2GB
• Secure Digital – up to 2GB
• Multi Media Card – up to 512MB
• xD-Picture Card – up to 1GB

This limitation could render the product unsuitable for many professional photographers, or those wanting to use it as a way to plug in fast solid state storage. For basic use, however, it is perfect — and priced at around $20.

SIIG FireWire 800

Sure the MacBook Pro comes with a Firewire 800 port as standard, but more ports could always be welcome. This adaptor provides two FireWire 800 (one 9-pin & one 6-pin) ports for multiple device connections and works with DV camcorders, FireWire hard disks, digital cameras, scanners, CD-RW/DVD drives, video game systems, and other audio/video devices.

The main problem with this idea is that Firewire devices already support ‘daisy chaining’. This is likely to reduce the need for additional ports directly in your laptop, though it is still common to have Firewire devices without an in-built second port. The SIIG Firewire 800 card is priced at around $85 — a comparable price to most FW800 hubs.

Note: I’m aware the above picture is for a different version of the device — the ExpressCard/54

Sonnet FireWire + USB 2.0

The ExpressCard card from Sonnet provides a simple way to add a USB 2.0 port and two Firewire 400 ports to a MacBook Pro. This is particularly appropriate and topical with all the dispute surrounding Apple dropping in-built Firewire 400 ports. With this card, it’s easy to connect to any of your old Firewire devices and also provides an additional USB port.

The card is priced at a reasonable $50 — not bad for reclaiming Firewire 400 support.

Any others?

I haven’t touched on one of the other major uses for ExpressCard expansion, that of adding a wireless modem to your MacBook. These allow you to connect a laptop to a 3G or EDGE data network, and they’ll be covered thoroughly in a future article.

Are there any other gadgets you find useful to fill your ExpressCard slot? I’m intrigued to know if I missed anything useful.

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