Power Amplifier Reviews

Setup & Real-World Performance
The first thing I noticed when placing the W4S amp in my equipment rack was its light weight. With its Class D design, there's no need for a large transformer and heat sink due to its more efficient design (83% efficiency at full output). The result is a "green" amplifier, which generates far less heat and uses less power than your typical Class AB amp.

Starting with 2-channel material and using the RCA inputs, I wanted to test the musical capability of the Ice Cube with one of my favorite songs—The Eagles' "Hotel California" from their album Hell Freezes Over on CD. Initially, I wasn't very impressed. The guitar solo that opens the song sounded a bit harsh, and when Don Henley's golden voice kicked in, it didn't sound as natural as it should have. But as the song progressed, the harshness disappeared and the imaging vastly improved.

I skipped back to the beginning of the song and sure enough, a little warm-up time enabled the amp to convey the true sound of the recording. Each pick of the guitar was precise, and the bass had its distinctive "thump." After this experience, I decided to leave the amp on continuously since it draws only 7.5 watts per channel when idle (37.5 watts total). The energy expenditure is a fair trade-off for superior sound at a moment's notice.

Next, I wanted to see how the W4S handled female vocals. My favorite female singer is Norah Jones—her debut album Come Away With Me is simply gorgeous, especially the title track. Her silky voice and the overall soundstage have never sounded better in my system. The seamless blending of the front left and right channels created a wall of sound with the subtle timbres of the acoustic instruments precisely placed across the front of my room.

My final 2-channel test had me reaching for some old-school rap, and there's none better than Kool Moe Dee's "I Go To Work." He's one of the most underappreciated rappers of the 1980s, but I really enjoy his up-tempo style and fast delivery. I like this particular song not only for its witty lyrics, but also its crisp highs and deep bass. The W4S amp didn't break a sweat with this challenging material played at reference volume. The vocals were clear and concise, stereo imaging was exceptional, and the dynamic bass was chest-thumping.

As much as I enjoy listening to music, my true passion is watching movies. I put the Ice Cube through its paces with a wide variety of soundtracks and expected nothing but pure audio bliss after hearing what it could do with stereo recordings.

I wasn't disappointed. Top Gun is one of my favorite movies from the 1980s for many reasons—most of all for its kick-ass soundtrack and the air-to-air combat scenes. The Blu-ray release includes a Dolby TrueHD and DTS-HD Master Audio soundtrack, and both were very impressive in the company of the Ice Cube MC. Discrete effects flew around the room with precision, and the roar of the jet engines placed me in the middle of the action.

Another demo favorite of mine is Disney's Pirates of the Caribbean: At World's End on Blu-ray, with its stupendously complex and aggressive 24-bit PCM 5.1 soundtrack. The track is richly textured and features a full 360-degree soundfield. The W4S handled the mix with ease, even at reference levels, with crisp dialog, subtle effects, and thunderous dynamics when needed.

As a final test, I unhooked the amp from my system and brought it over to a fellow enthusiast's home. He was breaking in his new Revel Performa F52s, which are superb-sounding speakers. I wanted to see how well the Ice Cube handled full-range speakers and to hear his impressions of the amp.

We used a Denon AVR-4806CI as a pre/pro and connected the front left and right channels with RCA cables. I let my friend choose the music, and after about 40 minutes, he came away just as impressed as I was. He described the amp as "clean, clear, and transparent," which matches up perfectly with my impressions. He was also amazed at how cool the amp was after the demo—it wasn't even warm to the touch!