CES 2013: Unison Research and the UPower Tube Booster Amplifier







Like many audiophiles, I wish that my flea-powered amplifier wasn’t quite so … anemic … when it came to modern loudspeakers. I mean, if it wasn’t for all the crazy-low impedance swings or sub-90dB sensitivity ratings, SET amps might still be relevant. Sadly, most loudspeaker designers could give two farts about all that — and I suppose that an argument can be made that blah blah blah sound quality blah blah blah. Whatever. The upshot is that most SET amps are pretty much useless, unless you opt for some wildly compromised or terrifically marginalized product to pair them with. Yes, yes — there are some manufacturers that “do that” sort of thing (Zu Audio and Rethm spring to mind), but the sad fact is that the average Dynaudio, Wilson, or B&W will never sparkle with 8 watts — it’s long past time to get over it and move on, right?

R-i-i-i-i-i-g-h-t.

Well, not so fast. Maybe not.

Enter the Unison Research Unico UPower amplifier, shown here in a rather unassuming black box and positioned directly below the very comely $2,495 Simply Italy integrated amplifier in a cleverly elegant stackable Splintr Designs Trellis rack ($2,000, as configured). An El34-based SET amp, the Simply Italy is “good for” 12wpc, which is plenty with just about any loudspeaker — assuming that it has a sensitivity of 95dB or higher. The very shapely (if you’re getting a vibe about the look and feel for the gear in this room, that’s not an accident) Opera Grand Mezza loudspeakers ($2,795/pair) are only 89dB. Common wisdom would tell you that this is not a match. Tone should be “just fine”, especially through the mid-band, but turn it up and you should expect the bass to flabbify, the treble to turn glassy or hard, the imaging to collapse, and cats and dogs to suddenly opt for cohabitation (or something equally horrible, YMMV).

Now, with the UPower, that changes a bit. Wire the amp into the “booster” and the booster into the loudspeakers and that 12 watts becomes 48. Ta-da! And yes, Virginia, 48 wpc should be more than enough to rock your world — with an 89dB loudspeaker.

Sounds great, no? Sure! It also sounds familiar. But wait:

There are already some “booster” amplifiers on the market, but they use the amplifier with a dummy load (typically a fixed amount of resistance) to produce only an amplified voltage output. These “booster” amps are characterized by a suitable voltage gain. In this way, however, the character of [the] sound due the [original] amplifier … is completely lost.

The Upower does not use a dummy load. The amplifier is always loaded by the actual impedance of the speaker; the voltage and the current that the amplifier provides are both simultaneously amplified by the Upower. This [is] a true “amplifier of power,” having both voltage gain and current gain well defined. The sensitivity of the amplifier to the impedance of the speaker remains unchanged as the speakers “appear” as directly connected to the amplifier output terminals, an operative condition that, as already stated above, [maintains] the character [of] the sound.

Okay. I’m curious. Where’s mine? Price is $2,695 in silver, $2895 in black. A Unison Research Unico CDE player ($4,120 with dual mono DAC upgrade) provided the tunes. All speaker cable, ICs and power cords came from the Cardas Audio Clear Light line.