For the last unseasonably cool hour, I've been sitting on my back patio, doing work, taking a short break to read a little Head-Fi, and now typing this. All the while I've been out here doing these things, I've been listening to my Sony SCD-C333ES CD/SACD player spinning all of Nick Drake's albums. No, I don't have a patio rig fronted by a SCD-C333ES, but I do have this player in my rig downstairs that I'm now tied to only by the ether tether of wireless headphones. Yes, I, a user and occasional reviewer of rather pricey audio cabling, am listening to a wireless headphone, which I've had occasion to listen to nearly as much as my dedicated home headphone rig. What am I listening to? AKG's very impressive HEARO 999 Audiosphere II digital wireless headphone system. Immediately upon its arrival, the HEARO 999 made strong first impressions--even before it was unpacked, installed and listened to, because the AKG HEARO 999 Audiosphere II system arrived in a chic (well, chic to a headphone geek anyway) hard-side, industrial-looking case, adorned with a gigantic AKG logo (I can imagine AKG fans wondering how they can obtain these cases separately, for which I have no answer). Within the case is a generous kit, including the HEARO processor/transmitter box (I'll hereafter refer to it as the "HEARO box"), the HEARO digital receiver/headphone (hereafter referred to as the "HEARO headphone"), two AC adapters (one for the HEARO box and one to recharge the HEARO headphone), a pair of good high-output AAA rechargeable batteries, two different kinds of analog interconnects (one pair of RCA-RCA and one RCA-RCA-miniplug), a mini-to-1/4" stereo adapter, a toslink optical cable, and even a set of pleather earpads (in addition to the velour ones that come installed on the headphones). Like I said, the case houses a generous kit. Here's a description of the setup for the two main parts of the review (two-channel audio and multi-channel home theater): To set the HEARO system up for audio-only (two-channel) evaluation, I took the CablePro Tracer v.2 coaxial digital cable and plugged it back into the MSB Gold Link III / Power Base DAC system, which in turn is driving a Meier Audio CORDA PREHEAD, and then used the PREHEAD's loop-out to drive the analog inputs of the HEARO box. This setup allowed me to easily compare wireless to wired using the same source components. Additionally, for two-channel music-only evaluation, I chose the HEARO box's “DIRECT” setting, which bypasses all of its signal processing functions. For home theater evaluation, I set the HEARO system up in the home theater/secondary audio system, with the HEARO box accepting the coaxial digital output of my Motorola DVR/HDTV cable tuner, and the TOSLINK output of my Sony DVP-NS500V SACD/CD/DVD player. For television and movie watching, I chose to let the HEARO automatically decode Dolby Surround Pro-Logic or Dolby Digital (based on what’s available, with Dolby Digital auto-selected by the HEARO system when available), with the the HEARO box’s IVA (Individual Virtual Acoustics) processor providing surround sound through the HEARO wireless headphones (or any headphones plugged directly into the HEARO box). And since my home theater system only has two loudspeaker channels, I also used the HEARO box’s built-in VMAx processor, which is a DSP circuit designed to enable a single pair of loudspeakers to emulate surround sound (again, using either Dolby Surround Pro-Logic or Dolby Digital, depending on what’s available). Using the HEARO 999 System for Music (Stereo) In consideration of its wirelessness, I can't imagine you'd be surprised if I said that the HEARO system doesn't quite keep up with my dedicated, fully-wired desktop rigs in terms of absolute fidelity. But get that expectation out of the way, and you're left with a wonderfully satisfying hi-fi wireless lifestyle product that, in comparison to wireless headphones I've heard so far by Sony, Sennheiser, and FreeSystems, probably represents the current state of the art--maybe even by a wide margin. In fact, I think it more fair to compare the HEARO system with wired rigs than to compare it to anything else wireless that I've ever heard, as it's that sonically capable. For a few years, what I’ve been using for wireless headphoning is the good-for-a-wireless-system FreeSystems xdream. On balance, it was one of the better sounding wireless headphone systems I’d used until now, so I made sure to keep the FreeSystems xdream handy throughout the HEARO evaluation for comparison. As nice as the xdream is for what it is, it was obvious from the start that the HEARO is far and away the the higher fidelity of the two systems. Since I can’t use the headphone from the xdream system with the HEARO system (and vice-versa), it’s hard to tell where the HEARO makes the bulk of its gains in performance versus the xdream. That is, is the HEARO system's advantage obtained mostly from the digital technology and implementation used? Is it mostly the headphone itself? Or is it a combination of both? Since I can't say for sure, I can only guess that it’s a combination of both; but I would suspect that AKG’s decades of expertise in developing and manufacturing high-end headphones probably points to significant advantages over the xdream, where the quality and design of the headphone is concerned. First of all, the large size of the HEARO headphone belies its long-term comfort. Weighing 12.4 ounces, it's not exactly featherweight, but, as anyone who uses full-size AKG headphones will tell you, AKG knows how to make comfortable full-size headphones, thanks in large part to their auto-adjusting headbands, just the right amount of squeeze tension, and ample padding over the ears. It is no hard labor for me at all to keep the HEARO headphone on for long periods of time (which I've now had countless occasions to do), which I definitely could not say about the xdream. In terms of fidelity, how do the xdream and HEARO systems compare? Again, it's not even close. In my setup, the xdream sounds like it adds unnatural, uncontrolled thickness to the bass region's midsection, and exhibits a thinness in the upper midrange. I can clearly sense the xdream's frequency response peaks and troughs, and, though certainly tolerable (only considering it's wireless), it makes unnecessary any reminder that I'm definitely not listening to one of my wired rigs. Timbral reproduction from the xdream is just as inconsistent as its frequency response, reproducing, for example, some of the wood tones from a cello's lower registers, but losing that wood color almost completely at the cello's upper range. Wide-ranging piano pieces suffer a similar timbral fate. Large-scale orchestral works have their luster dulled by the xdream's limitations, projecting only a silhouette of the whole, the orchestra's full color palette diminished significantly by the xdream's inability to pass all the musical information that imbues each instrument and instrument group with their own identities as components of the whole. In short, the xdream obscures the fine details, and fails to deliver the nuances that so many folks here spend significant sums of time and money to obtain from wired rigs. Again, these are sins that were once forgivable because the xdream is wireless, its primary purpose to allow one to walk around the living room while listening; but the latest HEARO system makes very clear that accepting such a high level of tradeoffs with wireless is now a thing of the past. The HEARO has a far smoother, more coherent presentation than the xdream across its entire frequency spectrum, and, again, is certainly more akin to a good wired system in this regard than it is to previous expectations I had of wireless headphone systems. Broad-spectrum, full orchestral works, like Mahler's 5th, are presented with a good sense of even-handedness, with no instruments being artificially thrust to the front or pushed to the back like the xdream can do with its seemingly peaky-troughy frequency response. Though it's certainly no Meier Audio CORDA PREHEAD/HD650 when it comes to performance in the lower registers, the HEARO's bass extension is good, with a moderately impactful physical sense, but certainly not the energy, snap and solidity of my wired desktop rigs--don't get me wrong, though, as, for a wireless system, its bass performance is musically very good and very tuneful. The now audiophile-famous Gladiator score--its third track ("The Battle") an audiophile standard for its all-out assault on one's rig (it doesn't hurt that it's good, fun music, too)--evidences the HEARO's limitations in terms of bass reach, the thundering percussive at 03:00 audible, but lacking some of the Thor's-hammer impact you can extract from this recording on an exceptional wired rig. When tuneful bass counts more than visceral thunder, the HEARO is more in its element, making easy work of the rapid-fire stand-up bass of Michael Arnopol in "Use Me" on Patricia Barber's Companion album. If you're a jazz fan looking for a good tuneful bass test, by the way, this is a must-have track, the opening of which has revealed for me many a system's limitations (especially loudspeaker-driving systems and their rooms) as far as tuneful bass performance goes--the HEARO, however, passes this test with aplomb, with good bass pitch definition, timbre, and adequate speed. (SIDE NOTE: Michael Arnopol is also an audio enthusiast, and is registered here at Head-Fi, though I think it has been a while since he's checked in.) The HEARO headphone's midband is, for the most part, pretty neutral sounding, but can become more prominent than neutral if you turn the volume up loud, especially with busier, densely-packed music. At volume levels louder than my tolerance will allow for any reasonable period, the bass seems to take a step or two down in relative amplitude, likely due to the limited power reserves of the built-in amplifier, which makes the midrange sound a little more prominent when listening very loudly. On material with more breathing room--a jazz piano trio, for example--the HEARO's midband seems quite neutral, regardless of volume level. As a listener of mostly acoustic music, timbral reproduction, to me, is absolutely one of the most important aspects of a rig's abilities. A rig that can reproduce timbre well across the audible spectrum can convey the essence and spirit of acoustic instruments, whereas those that can't impart an electronic glare that can reduce a Steinway concert grand to little more than a poorly synthesized attempt at one. The HEARO is the first wireless headphone system I've ever heard that actually has nice timbral reproduction across the board. Rostropovich's performance of the Bach Cello Suites, for example, is conveyed nicely by the HEARO, with the cello's organic wood resonance never lost, regardless of which notes on the cello the virtuoso excites. Also, the HEARO system does a satisfactory job of conveying air and space, but, not surprisingly, doesn't threaten my good wired rigs, some of which can sometimes reproduce a sense of physical space so eerily well that the hairs on the back of my neck stand up. The HEARO system's imaging is also good, with sonic images more rooted than floating (very impressive for a wireless system), but lacking the some of the holography of very good wired rigs. That this system can wirelessly convey the amount of musical information that it does is nothing short of astonishing, especially given the many inherent roadblocks that wireless can present relative to the demands of seasoned audio enthusiasts/snobs like us. The biggest weakness of the HEARO system is something that's hard to fault it for, which is, again, a mild sense of compression at what are (for me) painfully loud listening levels. Consider that we're talking about a wireless headphone that has, contained within it, a radio receiver/DAC (remember, the wireless transmission is digital), an amplifier, and, of course, the transducers--all powered by just two rechargeable AAA batteries. Consider my main wired headphone rig, in contrast, which has a dedicated AC circuit serving it, two balanced power transformers (to separate digital components from analog ones), a dedicated outboard DAC with a power supply that, by itself, weighs twice as much as most CD players, a class A headphone amp that has a maximum output measured in watts, and one of the most respected headphones in Head-Fi'dom, all plugged in and strung together with high-end cabling that alone has a total retail value more than twice that of the entire HEARO system. Long story short on this point, I can forgive a bit of dynamic compression (at ear-splitting volume levels) from a wireless headphone system that contains substitutes for many of these functions, and that accomplishes it mostly within the very physically limiting headphone form factor, and powered by just two AAA cells. And keep in mind I'm talking about volume levels I'd never actually listen at. The HEARO should get plenty loud, with little or no sense of dynamic compression, for just about anyone with properly functioning ears. NOTE: I tried alkaline batteries with the HEARO, but I don't recommend them, as the performance drops off considerably with time. The much flatter discharge curve of the included NiMH AAA cells that come with it (or any other good NiMH AAA cells) results in consistent performance throughout the charge (and, as often as I use the HEARO, the rechargeable batteries will save a lot of money in battery costs over time, too). Using the HEARO 999 System for Video and Movies (Surround) First of all, remember that this is Head-Fi, not Secrets of Home Theather and Hi-Fi, and I'm a diehard Head-Fi'er, so, for me, the HEARO's prowess as a multi-channel home theater device is secondary to its performance as a two-channel audio product. And, if you couldn't tell in the part of the review that precedes this, the HEARO exceeds all expectations I've had of wireless hi-fi headphones for music-listening. As it turns out, the HEARO system has also proven enormously valuable as a home theater product. Why? Because where we watch television and movies is directly beneath my toddler son's room, and he currently goes to bed between 7:30 p.m. and 8:30 p.m. And though I have some sound insulation in the ceiling/floor between the home theater area and his room, low frequencies, at moderately-loud to loud volumes, can rumble and hum through it. Low to moderate volume levels are okay, but, c'mon, who wants to watch Jurassic Park or the big shoot-out scene in Heat at low to moderate volume levels? Also, it's not unusual for me to be up late, so having the television or a concert DVD on in the background occasionally, piped through the HEARO headphone, is fantastic. Through the HEARO headphone, surround effects, and a sense of out-of-the-head sound, are reasonably achievable, if you take the time to set the HEARO system up correctly. (This involves downloading a couple of test tracks from AKG's website, and using them to optimize the customizable settings on the HEARO box.) Without going into the setup details, the HEARO has several IVA settings to accommodate different ears, the intent being to provide a setting for anyone to individually optimize the out-of-the-head effect. And once you find your ideal setting, you can further customize the sound processing, with different venue simulation settings (like a very cavernous "Stadium" setting, a more intimate "Club" setting, and a "Hall" setting that's somewhere in betwen the two, none of which I used regularly), as well as several surround spread adjustments to close in soundtracks that might be more exaggerated, or spread out the ones that could use more opening-up. On those nights I feel like watching a movie long after the wife and baby have gone to bed, there is truly no better way (that's practical) that I've come across to preserve the auditory impact and excitement of the movie experience than the HEARO system. Does it do a good job processing surround effects through the headphones? Yes, absolutely. Does it take the sound completely out-of-head? No, but it's definitely more out-of-head than with any non-HEARO movie headphone listening I've done. Bass performance (so crucial to fully enjoying many movies) is good, as long as you don't unreasonably expect these headphones (or any headphones for that matter) to physically manhandle you like your subwoofer does. But, as with music, something that good headphones can excel at is detail retrieval, and the HEARO headphone is no diferent--you will almost certainly hear details and nuances never heard before when watching your favorite shows and movies through the HEARO headphone. Discovery HD's show Destination Sunrise is simply an HDTV showcase of beautiful nature scenes (a variety of sunrises) and the corrseponding sounds. Sometimes I'll turn this show on for nice background imagery and relaxing soundscapes. With the HEARO headphone on, you hear everything--the bugs, the wind, the rustling grass, the water, and the tiniest details of all these things--so the experience is very immersive. In some action movies, for another example, I can clearly hear shell casings rolling on the floor under the din of gunfire and the whoosh of propwash from helicopters. Watching sports with the HEARO, I hear things like the echoes of skidding basketball shoes (and sometimes also basketball players' on-court banter), the scrape/shuffle of sliding tennis shoes, and the sliced air around a swinging golf club, with more clarity than I've ever heard before. In short, the HEARO system illuminates acoustic details of shows, events and movies like good HDTV allows visual details to pop with clarity and precision. While the performance of the HEARO system's headphone performance alone makes the system worth its price, it comes with a few added bonuses. The first two are for two-speaker home theater folks like me. The first is called VMAx, which is designed to simulate surround sound using only two front loudspeakers. Even if you're a little outside of the speakers' sweetspot, VMAx does a fine job of creating an expanded stage that's nice for movie watching. If you're right in the sweetspot, however, it actually can achieve the audio illusion of sound coming from the side and behind you, so I have VMAx switched on whenever I'm using the loudspeakers while watching movies or television shows (I turn it off, however, when I want to listen to music through the speakers). Another cool feature is the dynamic compression that simply reduces the dynamic range of whatever it is you're playing through the HEARO system--this is very helpful when others have already gone to bed while you still want to listen to your movie or television show through the loudspeakers. Simply put, dynamic compression helps blunt the amplitude of explosions and gunfire while raising the level of quieter passages, meaning I don't have to turn down the volume as much during louder scenes to the point I can barely understand dialogue. If trouncing my previous wireless headphone sonically wasn't enough, the HEARO system distances itself further by using digital radio frequency transmission instead of infrared. With the infrared xdream, my listening area is limited to places no further than about 20 to 25 feet out, and visual line-of-sight, from the xdream's infrared tranceiver pod. In contrast, the HEARO system's radio frequency transmission goes through walls, floors and ceilings, and uses antenna diversity (two antenna elements within the HEARO headphone) to decrease radio frequency drop-outs and dead spots. I can go anywhere in my house, and even out to the front and back porches, and still maintain acceptable reception. When stretching the distance between headphone and transceiver a little further than that, signal drop-outs are only occasional and very brief (usually less than one second), and are handled nicely by the system, which soft-stops and soft-starts the sound after signal disruption, making the relatively rare signal breaks gentle on your ears. Battery life is also good, never once having run down during my listening sessions that begin with a full charge. I would guess that five straight hours on a full charge, at moderate to moderately loud volume levels, would be a realistic expectation. I have kept an extra set of batteries charged and at the ready, and haven't had to use them once yet. (I would, however, recommend keeping an extra set of batteries charged if, say, you've taken a sick-day and plan to use the HEARO all day.) Wireless HEAROics, The Conclusion The AKG HEARO 999 Audiosphere II digital wireless headphone system, with an MSRP of $1,199.00, is obviously at the top-end of the price scale for wireless headphone systems (call our Sponsors for their best pricing). Fortunately, its sonics and features place it at the top-end of the wireless headphone performance scale, too. As the only truly musical wireless headphone I've heard so far--coupled with its oustanding home theater capabilities--AKG's top-of-the-line wireless headphone system is an excellent value, and, based on my experience with wireless headphones, it may currently be without peer. As I stated, its performance as a wireless music playback system may be where most of the HEARO System's value will be realized by the likes of a serious Head-Fi'er. And to sum up this review, I'm going to give an example of just how good it is: When listening to the xdream headphone, if I happened to venture near one of my wired rigs, the xdream's sonics never had me inadvertently reaching for my headphone amp's volume knob when I wanted to adjust the volume--that is, the xdream performs and sounds so different from (read: inferior to) my wired headphone rigs that my brain just can't mistake it for a wired rig. But when I'm listening to the HEARO headphone, and happen to be within arm's reach of a wired rig, I regularly reach for my amp's volume knob to adjust it up or down, only to realize (when the volume doesn't change) that I've got the HEARO on my head, and not one of my wired cans--I can’t imagine a higher standard for wireless headphone fidelity than to be mistaken for wired. PROS: Excellent sound quality and musicality; wireless freedom; RF-based (instead of infrared); headphone is comfortable; easy setup; Dolby Digital decoding; home theater sonic dramatics even after the kids have gone to bed; Dolby Digital surround emulation for two-channel speaker rigs. CONS: Expensive; no remote control to switch between source inputs or to adjust processing settings; you might experience short battery life if you listen loudly.