Power Amplifier Reviews

Performance
Features
Ergonomics
Value

AT A GLANCE
Plus
Exceptional performance
Exceptional build quality
Dimmable power indicator light
Minus
Pricey

THE VERDICT
It doesn’t come cheap, but NAD’s Masters M28 is a genuinely unique product designed to compete sonically with some of the highest-end amps on the market, regardless of how many channels they offer.

Whether you fall into the "all well-designed amps sound the same when used within their limits" camp or the "amp selection is critical" army of true believers, it's arguable that prior to the turn of the millennium amps designed for high-performance audio had fallen into a rut. They were so good that the advertising for them had to become increasingly creative. But a parade of skilled designers remained convinced that the new concepts they had come up with were superior, and audiophiles still lined up to buy them. The turf was always familiar: tubes remained tubes with their lovable quirkiness, and solid state was dominated by class-A/B designs as it had been since the transistor was invented.

Performance
Features
Ergonomics
Value

AT A GLANCE
Plus
Solid performance
Flexible 4-, 2-, or 3-channel setup
Five-year warranty
Minus
Intrusive rear-panel lighting

THE VERDICT
The Avalon G4 may be designed for upgrading systems to the new immersive audio formats, but it's also a fine performer that's flexible enough to satisfy other configurations.

Four may be an even number, but a four-channel amplifier like AudioControl's Avalon G4 might seem like an odd duck to some. With Dolby Atmos and other immersive audio formats becoming more common in the custom install market (where AudioControl, which manufactures products at its Seattle facility, has a heavy presence), however, upgrade-anxious customers will obviously need four additional amp channels to complement the company's existing 5- and 7-channel designs.

Performance
Features
Ergonomics
Value

AT A GLANCE
Plus
Class-A sound with improved efficiency
Exceptional transparency and control
Minus
Not the most powerful amp on the block
Display unnecessary for most users

THE VERDICT
Krell returns to form with an exceptionally capable amplifier for well-heeled home theaters where quality takes precedence over quantity.

It's hard to overstate the importance of Krell Industries in the history of high-end audio. Founded by Dan and Rondi D'Agostino in 1980, Krell was the audio equivalent of Lamborghini—an audacious riposte to more Ferrari-like rivals such as Mark Levinson and Audio Research. For almost three decades, Krell went from strength to strength, introducing a stream of ever more ambitious products that tested the depth of their customers' pockets, along with the strength of their audio equipment shelving. Then, starting around a decade ago, the brand slowly slipped off the radar screens of most audiophiles.

THE VERDICT
Emotiva’s BasX surround processor, five-channel amp, and speakers offer an affordable and high-performing starter system that puts you into audio separates without breaking the bank.

Surround separates are generally regarded as a step up from receivers. If you want the biggest and best, and have to ask their prices, you probably can’t afford them. But ask me the prices of Emotiva’s new BasX surround preamp/processor and multichannel amplifier, along with a set of compact speakers from the same series. The answers are $599, $499, and $1,045, totaling $2,143 for a 5.1-channel system of electronics and speakers. That would buy a midpriced receiver and a decent (but probably smaller) satellite/subwoofer set.

AT527NC Amplifier
Performance
Features
Ergonomics
Value

AT524NC Amplifier
Performance
Features
Ergonomics
Value

AT A GLANCE
Plus
Very powerful
Natural and balanced
Made in the U.S.A.
Minus
LEDs are too bright

THE VERDICT
The days of looking down on Class D amps are over.

Two and a half years ago, I reviewed my first ATI amplifier, and to say I was impressed would be an understatement. The ATI Signature AT6005 five-channel amp set a new benchmark for its designer, Morris Kessler—to the point where he put his John Hancock on the faceplate.

Last year, S&V editor-at-large Bob Ankosko sat down with Kessler to talk about his design philosophy over the years, and the subject of Class D amps was broached. Kessler mentioned that his current designs were all Class A/B, but he was following the developments of Class D very closely—though the initial efforts in this area didn’t meet his high standards because frequency response varied greatly as the impedance of the speaker changed. He hinted at the time that he may have finally found a Class D solution that he could deem acceptable, which turned out to be the latest Hypex Ncore modules.

Performance
Features
Ergonomics
Value

AT A GLANCE
Plus
A new take on amplifier classes with iBias
Superb dynamics and soundstage
Ethernet capability for system monitoring
Minus
LED illumination too bright
Extremely heavy

THE VERDICT
Krell’s iBias technology has allowed them to deliver the benefits of a Class A multichannel amplifier in a way that will have audiophiles grinning from ear to ear.

Do you remember what it was like sitting for your high school or college lessons? Well, get ready for a trip down memory lane, because to give the Krell Chorus 7200 the praise it’s due and explain just how much this “little”-amplifier-that-could is going to change the audio industry, we’ll need to start with a short class in “classes.”