Integrated Amp Reviews

The SM-SX100 didn't need to be turned up to sound "alive." Yet when I did crank it, it never hardened or glazed over. Still, I found myself using my SPL meter—I frequently turned the volume up way too high because the amp sounded so good, and behaved so well when asked to deliver high SPLs. At high levels, the top end did get to be a bit much, but that will happen with any amplifier. What didn't happen with the Sharp was dynamic compression, image smearing, or flattening—though, of course, the Amati Homage's sensitivity is about 93dB. The SM-SX100's volume control goes to 128. I never took it above 45.

So much for LP. What about SACD? The Sharp takes the SACD bitstream directly in and amplifies it in the digital domain, so you'd expect the sound to be amazingly pure and transparent.

It was. I auditioned all the SACDs I could get my hands on, including Mobile Fidelity's hybrid of Duke Ellington's Blues In Orbit, and Sony's discs of Miles Davis' Sketches of Spain and Kind of Blue. The results were transcendent. I've heard SACD criticized for being too airy and open—as if that was an artifact of the process and not part of the recording. I don't know if I can agree with that after this audition, in which I A/B'd the Classic LP and Sony SACD of Sketches of Spain. Yes, both were digitized—one before being etched in polycarbonate, one in the SM-SX100—but even taking that into account, they sounded remarkably similar.

In the end, I preferred the SACD to the LP—it was slightly quieter, purer, more three-dimensional. In fact, it was the best playback of Sketches I've heard. I turned the lights out and listened all the way through without growing bored. The amp's rendering of the castanets was absolutely riveting.

The necessity of the extra step of converting PCM sources to 1-bit was somewhat troubling, but of course that can be avoided by using your CD player's analog output, which would then be DSD-encoded by the Sharp's delta-sigma modulator. I ran the analog, PCM, and SACD outputs of the prototype DX-SX 1 SACD player Sharp lent me into the SM-SX100. The amp's input switching is configured to route both the SACD digital and analog outputs to the SACD selector button on the front panel so you can listen to SACD or CD without switching inputs.

While playing regular CDs, I A/B'd the player's PCM output (which first had to be converted to 1-bit before amplification) with its analog output, which was then DSD-converted directly, and found the PCM version slightly softened and muted compared to the DSD-converted analog. If I owned the SM-SX100, I'd avoid converting PCM to 1-bit.

Conclusion
I approached the $15,000 SM-SX100 with anticipation, excitement, and deep skepticism. I was eager to hear a new technology, but how much fun would it be listening to vinyl through a digital lens, no matter how good? How long would it be before I sensed I was missing out on all that my turntable, cartridge, and phono section were capable of delivering? I wondered whether Sharp was capable of delivering high-end sound through this—or any—new technology. To the best of my knowledge, Sharp, unlike Sony, had never even tried.

I kept the amp in my system for over a month and never felt like taking it out. I never did feel like taking it out. The SM-SX100 drew the best performance out of the Sonus Faber Amati Homages that I've heard yet—especially in terms of bass extension, dynamics, and control—though the Musical Fidelity Nu-Vista 300 is clearly in the same league. But while I love the Amati, it's not the most neutral or analytical speaker out there; how the Sharp will fare with a "flatter" speaker—or with your speaker, whatever it is—I can't say.

For the first time ever, if you can believe it, I actually liked the idea that the analog signal from the Audio Research Reference phono section was being digitized. I felt that it was being "archived" in real time, as DSD technology was originally intended to accomplish. There would be no further degradation as the signal moved through the reproduction chain. At least, that's how I felt while listening to music.

If you're a tube guy or gal, you might find the SM-SX100 a bit dry and lacking in harmonic complexity and bloom in the upper midrange, a bit dry in the mids, and maybe even somewhat aggressive on top, especially on bright-sounding recordings. But I don't think you'll be less than impressed by its micro- and macrodynamic performance, by its rhythmic swagger and ease, by its exceptionally solid imaging, accomplished transient delivery, or overall coherent sonic performance. This is an exciting product to listen to over the short or long hauls. And if you take the time to listen at very low levels, you'll be amazed at how the amps hangs together rhythmically where many just sort of ooze.

Too bad it doesn't have a few more analog inputs. Anyone with a turntable, a tuner, or other analog sources who uses the amp with a Sharp SACD player—or any other future brand that might include an SACD out jack—and who wishes to get the best CD performance, will be continually fumbling with interconnects.

But the look, feel, and build quality of the Sharp SM-SX100 are up there with anything I've experienced in the High End. It was a pleasure to use as well as to listen to. If you're the kind of audiofool who needs to have an impressive nameplate on your gear and the Sharp logo doesn't quite do it for you, go away. If Sharp keeps building products like this, you'll be back.