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Let's cut right to the chase in the best of Yankee slang: The Rx is one sick puppy, one baaad mutha. First, Ken's 30-pin-to-mini link bypasses the iPod's volume control and inferior headphone output stage. This bypass is not quite as total as tapping the SSD signal digitally such as the Wadia dock popularized and more and more devices are capable of now. But, it's clearly the next best thing in line.


Once your tunes are inside the Rx, the head scratching begins in earnest. How the heck can this little flat pack which piggybacks an iPod for a perfect fit generate the kind of drive to manhandle the big Sennheiser HD-800s or AKG K-702s as though they were nothing?

My stylin' First Aid Audio kit - Apple iPod Classic 160GB, ALO Audio Rx, B&O headphones. And before you ask, the pebbled leather lookalike Griffin Elan Convertible sleeves were recently procured at Amsterdam Schiphol during a 90-minute layover. I pried out the belt clips on the backs, then super-glued the two iPod-made pouches together, one oriented backwards to get the openings to line up as needed. Perfect and far cooler than linking the two machines together with rubber straps.

For quite a while, I've been suspicious about those battery-power claims which boast about noise-based superiority over conventional AC-fed circuits. Sorry, properly designed amplifiers like the Nelson Pass FirstWatt F Series for example might as well not be on. That's how spookily quiet they are even over very highly efficient speakers. Battery power has nothing on them. Never mind that class A operation for reasonable power doesn't exactly invite conversion to battery drive.

Still, battery-power line-level devices not asked to feed endless interconnects or punishing impedances can make persuasive cases for unbelievable drive into their targeted loads. It's here where I suspect battery power has been 'under-sold' to instead push freedom from the "evil" power grid. Batteries appear capable of delivering high current. And if there's one thing that drives transducers, it's current. This grasping for an explanation shouldn't be read as engineering fact. We'll leave that to smarter men properly qualified. Rather, consider it mere reflection on the delta of the perceived gap between size of Rx, seriousness of headphones and completely counter-intuitive results. In this class, I've only heard Ray Samuels devices which come close. And I'm not sure how high in his line you'd have to reach to find the Rx's equal.

Of course it's not likely that you'd shove an Rx into your coat or Jeans pocket only to sprout a pair of expensive Grado PS-1000s or Senn 800s in outdoors über-geek, er - fashion on your noggin. But since the arrival of the Rx in Casa Chardonne, I've often clapped just such headphones to my skull, grabbed a comfy seat and gone off to elsewhere whilst assorted speaker-based systems might have suggested greater appeal to most.


This remained true despite the fact that at the same time, our household contained 'grown-up' (i.e. non-portable) headphone amps from Woo, Yamamoto, Trafomatic, KingRex and Red Wine, all of them far more expensive, far bigger, far heavier and hence, far more serious. If you buy into such things. Most do.


The Rx is a very serious bit of engineering. Test the volume control all the way down to mute. Take note how the center image never shifts even the slightest. Inter-channel balance tracking is nailed spot on. Next move in the other direction. I guarantee you'll cry Uncle before you hit the ceiling even in lo-gain mode and on your gnarliest cans. Now pause your source. Noise? Only if you can hear the grass grow. The Rx aces all the basics. It also out-lasts my iPod on a full charge to satisfy even the hardiest of music consumers.


Fine you say. How's it sound? Not brash, strident, lean, thin, nervous, flat. Instead, it's unbelievably gutsy and potent 'all over'. Vinnie Rossi's Isabellina HPA with batteries at least 5 times the size of the entire Rx is mellower and expands the soundstage laterally and behind you in what goes for depth with headphone listening. The Rx casts sharper image outlines, shrinks the stage and has less whomp in the low end. That's on the wrong kind of headphones like the HD-800s with ALO custom wire. I call those wrong only because the appeal of the Rx is its portability. Earspeakers like the 800s are too big and expensive to really serve that purpose.



Once you slip valves into the equation—Trafomatic Experience Head One, Yamamoto HA-02—there are textures and tone colors which elude the Rx. That's not dissing the little fella, just keeping it real. More relevant than comparisons without regard for money is that listening over the Rx is amazingly satisfying. Coming off big headphone gear, it's really only stepping down from XL to M while remaining with the same brand of fine wear. The sound quality doesn't change. It's the audibility and scale of space which reduce; plus a similar reduction in overall weightiness and profundity. It makes the Rx version more intimate and lighter of gestalt. Because this doesn't involve any fundamental alterations or losses, the extras from the bigger gear are surprisingly quickly forgotten. It's this 'easy go' which most strongly validates the Rx. Unlike with speaker systems where one will be clearly superior to have you hankering such that memories keep intruding and diluting the smaller presentation, the Rx acts like an eraser. One forgets quickly even while those bigger amps keep eye-balling you with moist lashes.


Comparing the Rx to the current-gen iPod Classic's own headphone output is a step-down of far greater severity. It's about guts and glory vs. bleached and pale. Then my small B&O ear pods lack conviction and gumption to reinforce the Danes' style-over-substance reputation. Properly inserted over the ear canal to create a good seal and leashed up to the Rx however, they become all I'd ever want to take on the road to listen in an airport, plane or hotel room. Seriously.


That's because tonal fullness is properly centered and grounded, the treble sans annoyance even over long stretches and higher levels. There's no op-amp dryness, no chalkiness. The Rx scores high on rhythmic fare where it bounces rather than shuffles. This is supported by taut transient grip which also serves up high clarity without oversharpening. It's in the domain of subtle fades, of hall decay and ambient whispers where my big headphone rigs present more to get lost in. If I call that night-time listening—more introspective, chasing the inner game of music—the energetic Rx is tailor-made for day-time jams that focus on snap, impact and drive. For $345, ALO Audio's Rx Amplifier strikes me as a must-have for iPodders of all ages who either suspect that device capable of a lot more; or who happen to have audiophile friends who wholeheartedly applaud their voracious 'anywhere' musical appetites but pity their ignorance on what quality sound is all about.


Kudos to Ken Ball for contracting with veteran Matt MacBeth. He clearly is a master at this miniaturization game which maximizes performance to unexpected degrees. For this writer, Christmas came early this year. The Rx and iPod Classic have become inseparable, joined quite literally at the hip by super glue but also basic ear necessity. If the Ken/Matt duo can fulfill their dream of an iPod DAC in the Rx enclosure, I'll again reach for the glue and add a third layer to my current two-layer sonic sandwich. Definite award material. It's also one stupendous stocking stuffer for all generous audio Santas who look to spread the better-sound virus to the unsuspecting iPod nation. Better ear pods than Apple's will come next. But that would be a story for another day.

 

ALO Audio website