Solid State Power Amp Reviews

Beginning with the single C 298 driving the Revel Studio2 speakers, listening to several familiar selections, I found nothing remarkable, and I mean that in a good way. There should not be big, striking differences among high-quality amplifiers of sufficient bandwidth and power. Big differences make me suspicious that something's wrong or that something's not fair. It was reassuring to find that the NAD was fully up to the task, but this does make characterizing an amplifier's sound challenging.

By unexplained providence, there have been two new releases of French chamber/parlor music for piano and a string instrument, both claiming inspiration from Marcel Proust. And yet there is no overlap in the selections, and there's very little overlap in the aesthetic. Although both string players employ instruments by Stradivarius, the piano on Proust, Le Concert retrouvé: A Concert at the Ritz during the Belle Époque (Tanguy de Williencourt, piano, Théotime Langlois de Swarte, violin, Harmonia Mundi HMM 902508, 16/44.1 WAV download) is an 1891 Erard, while the pianist on Music from Proust's Salons (Steven Isserlis, cello, Connie Shih, piano, BIS-2522, SACD, 24/96 FLAC download) plays a modern Steinway D. From the first note from the Erard on the HM recording, one is drawn, à la Proust, into a recollection of an earlier time. The instruments are warm-toned, the ambiance is intimate, and the pace is gracious. It feels personal.

Conversely, the sound of the instruments on the BIS recording (even in stereo) is more modern, the space more open, and the pace playful. It feels honest but, compared to the HM, more dynamic and also more distant. The NAD C 298 reveals those differences as two equally convincing perspectives and encourages listening to both for full appreciation.

With the larger ensemble size and dynamics of a modern orchestra, the C 298 is entirely up to the task as single stereo amp. Gianandrea Noseda's Shostakovich series with the LSO is gathering steam from a triumphant version of the Symphony No.8 to a new release of the 9th and 10th symphonies (LSO Live LSO0828, DSD64 download). I think of the 9th as the bigger, brawnier cousin of Prokofiev's "Classical" 1st symphony. Neither the snappy snare drum bursts of the first movement, the deep, weighty brass chords of the Largo, nor the chest-thumping tuttis of the finale prevent this piece from seeming happy and engaging. Still, these characteristics—and also the recording's wide dynamic range—present a challenge to amp and speakers. With either my Revels or the Dynaudio Confidence 30s (review on tap), a single C 298 in stereo mode handled it with aplomb, even at high levels. (My wife just slammed the door to the next room!) The NAD gave no indication of stress. It was barely warm to the touch.

On voices, too, the C 298 was excellent. For that, I went back to the Qobuz stream of "Sister Rosetta Goes Before Us," sung by Alison Krauss on her album with Robert Plant, Raising Sand (Rounder 11661-9075-2, CD). Yeah, same beautiful voice I know but a bit fleshier and with the abiding HF noise that accompanies it less obtrusive. Bass was big.

A single C 298 was excellent and capable, so why did I insist on getting a pair? Power! As a stereo amp, the NAD is about 2.7dB more powerful than my 100Wpc Benchmark AHB2, but I choose to use it bridged to 370W most of the time for headroom: peace of mind. The bridged NADs are rated at 620W, about 2.25dB higher than bridged AHB2s. The real pleasure is not that they sound different but the freedom to turn up the volume without trepidation.

I wanted to hear explosive dynamics. I picked two tracks. A classic system stressor is "The Garage Door or The Dynamic Range of Real Life" from Hi-Fi News & Record Review Test Disc III. JRiver says this track has a dynamic range of 17, but it punches (literally) way above that. Set the opening voice of Mike Skeet to normal voice level, and the crash of the closing door is very loud with a potent low-frequency bang! as the door hits the ground. But hang on: After Mike's slightly muffled announcement from the other side, he pounds sheet metal, making several raucous smashes! so loud that, even in midafternoon, I will not play it more than once for fear of retribution from neighbors. For the bridged C 298s? No sweat.

For an actual musical selection, I chose Hugh Masekela's live 1993 recording, "Stimela," from the album Hope (Analogue Productions APJ 82020, SACD), which JRiver says also has a dynamic range of 17. Here, the exuberance of the performance and the audience encouraged me to push the volume up to feel part of the event. Rather than stressing the NAD, it both startled and thrilled. A single, stereo C 298 might do the job, but that will depend on your speaker's sensitivity. It's always nice to have power to spare.

Compared with the PS Audio Stellar M1200s
Michael Fremer was impressed with these monoblocks with their 12AX7-based input stage and ICEedge class-D output stage. He made a provocative case for their combination of performance, power, and price. When Jim Austin suggested that, as a follow-up, I compare them with the NAD C 298, jumped at the chance. PS Audio's Paul McGowan was supportive, but review samples were scarce, and our time window was brief and that stock was slim. PS Audio PR rep Frank Doris volunteered his personal pair.

I refer those interested in the details to Mikey's full review. The M1200s each are rated at 600W minimum into 8 ohms, and the bridged C 298s come in at 620W—a fair match. Switching from the bridged NAD C 298s to the M1200s was a surprise, because the PS amp seemed noticeably bolder, brighter, and bouncier, terms that should be reserved for laundry detergents. Recalling what I said about being suspicious of big differences, I double-checked. Turns out—duh—that the M1200 has a fixed voltage gain of 30.5dB—5dB higher than the bridged NADs in fixed-gain mode. That's not a fair fight. Since the M1200 gain can't come down, I used the

C 298's variable gain control to turn it up to match the M1200. Once the gain disparity was eliminated, the sonic differences between the two amps were much smaller but still worthy of discussion. The M1200 was still a bit bolder and livelier than the NAD. The Masekela track came alive at a slightly lower volume. On Mahler's Symphony No.6 with Glen Cortese conducting the Manhattan School of Music Symphony Orchestra (Titanic Ti-257, CD), another musical and sonic winner of my long sonic acquaintance, there was little to choose between. Jerry Bruck's warm yet extremely detailed recording captures the rich ambience of Riverside Church with remarkable weight and bass detail. JRiver tags the last (and my favorite) movement with a dynamic range of 22! The music demands it. (Oh those hammer blows!) There was, again, little to choose from, but if forced to pick nits, I'd say that the bass with the C 298s had a bit more weight while the M1200s offered a tad better bass impact.

For voices, woodwinds, and other midrange stuff, the M1200 had a slight advantage in clarity, but just as often, the NAD was somewhat more coherent across and deeply within the soundstage. I preferred different amplifiers on different tracks, for different reasons.

These preferences shifted as I switched between the Revel and the Dynaudio speakers, and I often questioned conclusions I had reached before. Throwing the bridged Benchmarks into contention muddied matters further. It has been my go-to amp for a while, and I may be biased toward it as a reference. I think it has more detail across the spectrum than the other amps, but it may not be as even-tempered as the C 298 nor as lively as the M1200. Relative cost definitely favors the NAD.

Conclusions
The NAD C 298 is a transparent, uncolored, powerful stereo power amplifier. It can easily drive most speakers to levels that exceed domestic tranquility. A bridged pair extends the power capability further still. The NAD C 298 challenges more expensive amps and should impress discerning listeners regardless of budget.