On the plus side of the ledger, the iDecco amp delivers a rich, clear, and evocative sound with excellent soundstaging characteristics. When coupled with speakers that can be driven well by 40 Wpc, the iDecco amp can produce huge, three-dimensional soundstages that leave the sound of many modestly priced integrated amps in the dust. During my tests, I used the iDecco in conjunction with a pair of Monitor Audio’s superb (and quite easy to drive) Silver RX8 floorstanders ($2000/pair) and found the combination to be one of those rare instances of “sonic serendipity” where the whole was much greater than the sum of the parts. Think of it this way: you could buy an iDecco and the Monitor Audio speakers I mentioned above for about $3000, then add either a PC-based music server and/or an iPod as source components, acquire an obligatory set of high performance cables, and wind up with a music system that—I kid you not—could easily do battle with many of the five-figure systems I’ve heard at trade shows.
Good though the iDecco amplifier section is, however, I would say it is perhaps not quite as impressive as other elements of the product are. The main sonic differences you would observe between the iDecco amp and higher end powerplants (such as the NuForce monoblocks I used in my tests) involve the iDecco’s slightly reduced levels of resolution and detail from top to bottom and somewhat less tightly controlled and less deeply extended bass response. There is, too, a difference in sheer power output to be reckoned with (remember, the iDecco produces an honest 40 Wpc at 6 ohms, while the NuForce monoblocks each belt out 335 watts at 4 ohms). In practice, this means you’ll want to keep the iDecco’s power output limitations in mind and plan your speaker acquisitions accordingly.
But let’s keep things in perspective. While the iDecco’s amp section may not enjoy the quasi-giant-killer status that its DAC and preamp sections do, it nevertheless offers very solid performance and—more importantly—unfailing musicality for the money.
I can’t speak for you, but I sometimes enjoy playing well-made recordings that show unexpected combinations of instruments at play, partly because they draw your attention to the musical ideas being expressed, but also because they seem like celebrations of the sheer beauty of sound, itself. One such recording is Marilyn Mazur and Jan Garbarek’s Elixir [ECM], where two favorite tracks are “Bell-Painting” and “Talking Wind.” Both tracks employ distinctive high percussion instruments of various kinds, highlighting differences in the attack, voicing, and decay characteristic of each instrument as played within a reverberant recording space. On good equipment, the sonic effect of hearing these tracks is not unlike running your fingers through a treasure chest full of variegated jewels—so many different shapes, textures and colors to take in at once. On both tracks the iDecco not only did not disappoint, but positively excelled.
On “Bell-Painting,” the shorter and more delicate of the two musical selections, you initially hear a round of differently pitched small bells and chimes being struck, followed by a similar round of slightly deeper-pitched bells and gongs being sounded. The iDecco deftly captured the variations in attack between the bells, appropriately giving each its signature voice, and showing how decay characteristics help define the bells’ sound—with some fading quickly to silence as others continue to shimmer and ring for several seconds after being struck, their voices lingering and floating on the air. Most importantly, the iDecco captured—but did not overdo—the fundamentally metallic character of the bells, something that in practice is easier to say than to do on this revealing track (some amps, for example, make the instruments sound much too "dry," almost like bursts of white noise, which isn't right). The iDecco served up levels of realism and nuance that not many amp/DACs in its price range could muster.