Ellula Inflatable "Hot Air" Loudspeakers
While not wireless, here is another alternative for your speaker needs.
Ask any engineer about making tradeoffs, and they'll start talking about giving away capabilities in one area in exchange for strengthening capabilities in another. In computing, speed versus space is a typical tradeoff, meaning that extremely fast systems or implementations often require more resources and memory than slower ones. Power and portability is another pretty common tradeoff - more powerful, more capable systems tend to be relatively less portable than less powerful, less capable ones.
The Ellula inflatable "Hot Air" loudspeakers essentially trade off mass and weight in the interests of increased portability. Conventional loudspeakers use active speaker elements to reproduce sound waves as accurately and warmly as possible, but they also rely on the mass and sound conducting characteristics of their enclosures to help direct, strengthen, and add warmth and character to sound as well. By and large, the most powerful and best sounding loudspeakers are bigger and heavier than less powerful models, not just because of the size of their speaker elements, but also because of the size and heft of the enclosures inside which those elements are housed. In some speaker systems, high-end sounds are handled by small light speakers, supplemented by large, very heavy subwoofer elements that centralize all that weight and heft in one big package.
At the other end of the spectrum, the Ellula "Hot Air" speakers forgo massive enclosures entirely, opting instead for inflatable plastic conic sections that pick up sound from an active element at the bottom of a blow-up enclosure and direct it out the top. The Ellula enclosures get their rigidity and structure from being filled with air. And while that air is at room temperature, not really hot, Ellula must have decided to name its products based on the phrase used to describe output from those who like to hear themselves talk!
As you'd expect from a set of lightweight speakers, the low end suffers most in playback. Without any real mass to conduct, focus, or direct bass waves, the NXT SurfaceSound active elements at the bottom of each of these speakers must reproduce low sounds on their own. This produces sound output that is a bit lacking in bass, but works pretty well at the mid-range and the high end of the sound spectrum. When compared to a pair of 10-year-old Bose speakers, the Ellula units didn't sound too bad, but there was an audible difference in bass quality (the Boses sounded much better.)
That said, these speakers are extremely portable. Fully collapsed, they weigh less than 2 pounds (870 g), of which nearly half that weight goes to the 12V 250 mA transformer plug (about 13.5 oz/385 g.) Each of the speakers weighs 6.6 oz (189 g), and the amplifier/volume control unit comes in at 3.7 oz (107 g). The rig works through any standard 3.5mm headphone jack.
These speakers would be workable for itinerants who want a little better sound than notebooks can deliver from built-in speakers, those who wish to produce listenable public sound from an MP3 player, or for LAN party attendees who want to leave full-sized speakers and amps at home.
At a price of $25 (MSRP), they don't put much load on the Xmas budget, and they look pretty neat sitting next to a notebook or on either side of monitor. Visit ThinkGeek to pick up a pair for your cousin Elmo, or anybody else on your list.