One drawback to the USB DAC, however, is the need for a wired connection between computer, DAC, and audio system. Enter Micromega, who has cut the cord with a high-end wireless receiver/DAC that allows you to wirelessly stream full-resolution audio signals directly from your computer to your audio system. The new WM-10 operates over an 802.11n network and supports AIFF, WAV, ALAC (Apple Lossless), MP3, and WMA files. Micromega is based in France, and the company's products are distributed in North America by Audio Plus Services. The WM-10 has an MSRP of $1,595. 

The Hookup 

A product that streams audio from your computer to your stereo - "So what?" you may ask. The market is saturated with less-expensive network audio devices that accomplish the same thing. True. What Micromega aims to deliver is a higher level of performance combined with easy setup and use. We'll talk performance in the next section; in terms of setup and user-friendliness, the company has done a nice job of offering extremely easy setup for network newbies while still providing enough flexibility to accommodate more advanced options.

Unlike many network audio devices that are Windows- and/or DLNA-based, the WM-10 is an Apple-sanctioned product designed to work specifically and directly with iTunes (on either a Mac or PC). You don't need to load a third-party media player onto your computer or piggyback another software platform onto iTunes (although you can if desired). Micromega's wireless Airstream technology is essentially Apple's AirTunes, which Apple uses in its standalone AirPort Express wireless module. The fact that this is an Apple-friendly product will certainly appeal to a large segment of Mac devotees who have not, thus far, had as many options in the streaming-media category. (In the interest of full disclosure, my husband is a Mac tech, and my household currently contains three Macs, three iPods, and two iPhones; I would say I fall squarely in Apple fangirl territory.) For those people who don't wish to be constrained to iTunes, the WM-10 is also compatible with Rogue Amoeba's AirFoil software, which allows for the wireless transmission over AirTunes of all audio signals on your computer, enabling the use of a different music software platform. 

Because the WM-10 can create its own Wireless-N network, you don't have to add it to an existing home network--nor do you even need to have your own broadband network in place. (I can't imagine that users of this type of product wouldn't have a broadband network, but still...) Once again, if you don't mind doing a more advanced setup, you have the option to use your existing network instead. 

The box itself is a model of simplicity. The front panel contains only a single LED, and the back panel sports just three connections: one stereo analog output for those who want to utilize the WM-10's internal DAC; one coaxial digital audio output that allows for straight digital pass-through of the signal; and a power connection. This is a wireless-only product, with no Ethernet port for a wired connection between computer and WM-10. The included User Guide is a simple, four-page brochure with clear, easy-to-follow instructions. To perform a basic setup, you first connect the WM-10 to your audio system via the output of your choice (analog is recommended), plug it in, and power it up; the front-panel LED will glow blue when initialization is complete. Next, go into your computer's wireless network settings, find the "Airstream" wireless network, and join it with the supplied password. Finally, launch iTunes on your computer; at the bottom right corner of the iTunes window, you'll see an option to switch the iTunes audio output from the computer to the WM-10. That's it. Cue up your iTunes music and enjoy. You can add multiple computers to the network to stream content from different iTunes libraries (you can only stream one library at a time), as well as add a second WM-10 in order to stream the same content to multiple rooms. 

If you opt for the easy setup route described above, you're forced to disconnect your computer from your own wireless network to join the Airstream network. That means you lose Internet connectivity and any other network/streaming functions you may have in place for that particular computer. If you're investing in a high-end audio product like this, I would guess that you do (or at least should) have a computer that functions solely as an audio server, so it wouldn't be a huge issue to keep said computer on the Airstream network most of the time. If you don't have a dedicated audio-server computer, then you have two choices: Either jump between wireless networks as needed or perform a more advanced setup that allows you to add the WM-10 to your own WiFi network instead of the Airstream network. This requires you to do a hard reset and re-configure the WM-10; the full instructions are not supplied in the User Guide, but you can download a detailed PDF file from www.micromega-hifi.com that provides a very clear, step-by-step guide with photos. Because the WM-10 simply receives signals from a computer software program, Micromega doesn't include a remote. However, they do direct iPhone and iPod touch users to a free app that allows for control of iTunes via your handheld device. Simply called "Remote," this is another Apple-designed application that's easy to set up and works over the wireless network, so you don't need line-of-sight between computer and remote. I was able to successfully control the iTunes/WM-10 combo from anywhere in my home. As for the user interface, the Remote app basically mimics the iPhone's iPod player, so navigation will be familiar to users of that program. If you've added multiple computers to the Airstream network, you can switch libraries each time you cue up the Remote app, and the app does allow for volume control within the parameters of your audio system. In general, response to commands was quick and reliable, although the app was sometimes slow to find and connect to my iTunes library when I first launched it; you can speed up this process by selecting the "Stay Connected" option in the Settings menu, but this can drain battery life.

When evaluating any wireless audio product, sound quality and signal reliability are the two crucial elements. Let's begin with the latter. The WM-10's closed 802.11n network has an estimated range of about 300 feet. I tested the audio streaming using two different computers: an older PowerBook with an 802.11g wireless card and an even older PowerBook with an 802.11b card. While 802.11n is technically backwards compatible with 802.11g/b, the system did not work with my 802.11b-equipped laptop. I could add the computer to the Airstream network, but the audio signal would disappear after just a few seconds of playback. 

I had more success with my primary 802.11g-equipped laptop, even when I placed it upstairs in my living room while the WM-10 remained downstairs in the theater. I pretty much ignored the recommendations that Micromega offers in the User Guide regarding placement of the unit for optimum signal reception: They suggest that you place it in an open area and avoid putting it in a place that's surrounded by metallic surfaces. Well, my equipment rack is tucked back in an enclosed corner and uses three metal posts that surrounded the product. Even with these obstructions and the use of an older 802.11g card, signal reliability was generally very good. For the first several days, I simply let the system run for hours on end; in that time, I heard maybe two or three split-second audio dropouts. During the second week with my sample, I experienced no dropouts or other interference issues. I would expect even better reliability from a computer that's equipped with an 802.11n card. In fact, I recommend that, before you even think about investing in this type of product, you first make sure you've got yourself a current computer, with 802.11n, to function as your audio server. 

Now let's talk sound quality. When I first learned that the WM-10 employs technology found in the AirPort Express, I assumed that this product used the Apple technology for its wireless transmission and then employed its own DAC, given Micromega's experience with high-end CD players. I then learned from my Audio Plus Services rep that the WM-10 also uses the AirPort Express DAC, a Cirrus Logic 4344 24-bit/192-kHz DAC that's integrated into its custom Marvell Corporation chipset. I must confess, this revelation inspired much uneasiness, given the rather significant price markup between the $100 AirPort Express and the $1,595 WM-10. How do the two products differ? The first is in the design and build quality of the box itself. The AirPort Express is a small 3-inch module that plugs directly into a power outlet and offers a single mini-jack output that serves as both the analog and digital audio out. (The unit also has a USB port for wireless printing only and an RJ-45 port for connection to a modem.) The WM-10 has a rack-friendly design with a well-constructed chassis that features separate analog and digital outputs and a detachable power cord, allowing for the use of higher-quality cables across the board. To suppress noise, Micromega uses an R-Core transformer designed to very tightly filter the AC feed and has omitted the RJ-45 connection entirely. Finally and most importantly, Micromega has carefully selected its own clock circuit to better address the all-important issue of jitter reduction. 

Do these differences merit the price increase? The best way to explore that question was to do a direct comparison between the two products, so I headed over to my local Best Buy to pick up an AirPort Express. I fed analog audio output from each product into a Pioneer Elite VSX-91TXH receiver and used a pair of RBH MC6-CT tower speakers for the evaluation--not exactly an audiophile system, but a good mid-level combination that has served me well. To get an objective perspective, I invited my husband to participate in a blind A/B test, using AIFFs of some of my favorite demo tunes: "Time" and "Brain Damage" from Pink Floyd's Dark Side of the Moon SACD: pianist Lang Lang performing Rachmaninov's Piano Concerto #3 in D Minor on SACD; "Alligator Pie" from Dave Matthews Band's latest CD; "1979 Semi-Finalist" by The Bad Plus; "Goodbye" by Steve Earle; and "Back to the Earth" by Rusted Root. When the test was complete, we both agreed upon several things: We liked the DAC's sound quality in general, and we preferred the WM-10's performance over that of the AirPort Express, although the difference wasn't as pronounced on my system as I would've hoped. The dynamics and general tonal quality of various instruments sounded pretty similar between the two; where the WM-10 distinguished itself was in its ability to breathe air into the music and produce a more spacious sound that still had a nice sense of intimacy and musicality. 

The AirPort Express didn't elicit as emotional a response from me, as the soundfield always seemed out in front. The WM-10 also did a better job of bringing out the subtlest details, especially in dense tracks with a lot of instruments playing simultaneously. In certain places, it perhaps sounded a bit cleaner, as well. I also compared the WM-10 with two disc players I own: the Pioneer Elite BDP-95FD Blu-ray player and the Sony SCD-CE775 SACD player. The differences between these products and the WM-10 were more easily discernable, as each had its own tonal quality, among other things. Once again, the WM-10's performance won me over. In comparison, the Sony player seemed to jumble everything together in the soundfield and emphasize sheer dynamic ability over subtle phrasing. The Pioneer had a neutral flavor but came across as flat and a bit sterile, while the WM-10 had a more musical quality, with a sweeter sound that I found more inviting. 

Micromega's decision to build this product around iTunes and AirTunes means that the WM-10 has some limitations that are inherent to the Apple technologies. For one thing, iTunes (and by consequence, the WM-10) does not support FLAC files, the format of choice on many full-resolution download sites. You need to convert FLAC files to ALAC for playback through iTunes. To the best of my knowledge, AirTunes actually converts all file types to ALAC on the fly, so you can save some hard-drive space by importing files in the Apple Lossless format instead of AIFF or WAV. Furthermore, iTunes imports are limited to a sample rate of 16 bits and 44.1 or 48 kilohertz, and the AirTunes wireless technology only supports a sample rate up to 16/44.1. I say "only" as if that's not full resolution; 16/44.1 is full CD quality. However, if you have a lot of higher-resolution files (24/96 or 24/192) from sites like HDTracks.com or iTrax.com, you'll be better served by a wired USB DAC (since you can configure iTunes for higher-resolution output via USB). Should Apple choose to upgrade AirTunes to support higher-resolution audio, the WM-10 could accommodate it. 

Second, two conflicting schools of design have emerged when it comes to computer-oriented DACs: one says it's okay to add additional digital inputs to make the DAC more versatile, and the other says this is detrimental to performance and keeps connections to a minimum. Micromega falls into the latter camp and thus has not included any other inputs to allow you to connect additional sources to the DAC. 

Finally, the User Guide is so concise, it won't be of much help if you encounter any setup glitches along the way. As I mentioned, I set up two different computers for use with the WM-10. With the first computer, setup proceeded just as the User Guide laid it out, with no issues. With the second computer, however, iTunes did not show the little box in the bottom right corner that lets you choose between computer audio output and the WM-10. The User Guide makes no mention of this possibility, so I had to explore iTunes Preferences on my own to solve the problem. Should you encounter this, the fix is to go into iTunes Preferences, under Device, and check the box that says "Look for remote speakers connected with AirTunes." One other issue regarding the User Guide is that it mistakenly calls the iPhone control app "iRemote" instead of just "Remote." If you search the App Store for "iRemote" by mistake, you'll find another free app called "iRemote Suite" that lets you control your computer via your handheld. It's logical to assume that this is the app you want, but it's not. Micromega is aware of this issue and will hopefully correct the problem in future shipments.

In both performance and user experience, I really like what the WM-10 has to offer: It's easy to set up and use, has greater convenience than a wired USB DAC, and offers excellent sound quality. The questionable issue is its price, specifically compared with the AirPort Express from which it heavily draws. Yes, Micromega's contributions resulted in better performance to my ears, as heard through a mid-level home theater system. Would that improvement be even more noticeable and meaningful on a true audiophile-grade hifi system, enough to merit the price increase? That's hard to quantify.