The UFi UCube USB Powered Computer Speakers
Relative to the Harbeth HL-P3ES-2 speakers on my main computer rig, these things just don't compare. Well, duh! The Harbeths are powered by 150Watt class-D amps run from a serious pre-amp and DAC. The UCubes get both signal and power from the USB output of my laptop. The question is: what can you compare them to?
Not much, they're pretty unique.
The UFi UCube Portable USB Powered Speaker ($149)
Recently Jonathan Scull (a PR agent) shot me an email about a few things including the UFi UCube. I sent him back an email expressing my interest. He replied, "I’m not sure UCubes are for InnerFidelity… they’re mass-market items that focus like little bandits and throw a wide soundfield, but they’re only 3 and change square inches."
What Jonathan doesn't know (yet) is that InnerFidelity is about personal audio, not audiophilia. I'm into stuff that sounds good, sure, but I'm also interested in stuff that packs around easily, looks good, and delivers a lot for the money. The UCubes do that very nicely, thank you.
The UFi UCube is a pair of speakers that gets both their power and their audio signal over the USB interface from your laptop. All that's required is that the USB interface is able to supply 500mA --- most computers will do this, but some USB hubs will not.
The heart of the system is a complex integrated circuit originally designed by Audium Semiconductor, which shut down when it sold all its intellectual property to NXT. NXT changed it's name to HiWave late last year, and brought together its balanced mode radiator (BMR) speaker technologies and the new Audium chip in a system they have dubbed "DyadUSB."
The integrated circuit combines a USB receiver, DSP, DAC, switching power supplies, and class-D power amplifiers in order to deliver 15 Watts of "burst power" from the 2.5 Watts of available energy on the computers USB port. It does so by storing extra energy during the soft passages.
Balanced Mode Radiator (BMR) speakers are similar to regular cone speakers in that they have a voice coil suspended in a magnetic field provided by a permanent magnet. Unlike a cone speaker, the BMR uses a stiff planar surface as its radiator. The mechanical attachment of the voice coil to the driver surface is done such that it is attached at the point of the first primary modal oscillation, and small weights are added to the rear surface of the stiff diaphragm to balance its moments (hence, "balanced" mode radiator) and control the dynamic performance of the diaphragm. At low frequencies, the surface simply pistons in and out; at higher frequencies the surface bends, and sound begins to appear to radiate from closer to the center of the diaphragm.
The result is a single speaker that doesn't suffer from "beaming" as the frequency increases. BMR speakers look more like a point source over their operating range than traditional cone speakers, and, as a result, a single driver can deliver what previously would have needed a cone and tweeter drivers and crossover. BMR drivers, therefore, deliver both wide frequency range and wide dispersion.
Lets have a look at the product itself.