June 2008 Reviewed by Roger Kanno	Axiom Audio A1400-8 Multichannel Amplifier

Description Model: A1400-8 Price: $3850 USD Dimensions: 18"W x 4"H x 17.5"D Weight: 54 pounds Warranty: Five years parts and labor	Features Highly efficient switching design 8 channels Manufacturer power ratings: 350W into 8 ohms or 1400W into 2 ohms (1 channel driven), 200Wpc at all impedances (7 channels driven) Die-cast aluminum chassis Inputs: XLR, 1/4" phone, and RCA (with provided adapters) Custom MOSFET output devices Massive toroidal transformer 140,000µF of capacitance DC trigger

The name Axiom Audio will be familiar to most readers. Their high-value loudspeakers have been favorites among SoundStage! Network reviewers for years and have won many awards, from us and other publications.

A few years ago, Axiom set out to design and build a line of ultra-high-performance subwoofers, for which they developed massive aluminum drivers and highly efficient and powerful switching amplifiers. I reviewed the largest model, the EP600, and found it a reference subwoofer worthy of inclusion in a very-high-performance home-theater system. Axiom’s president and chief designer, Ian Colquhoun, decided that the amplifiers used in the EP subs were so good that he would develop a line of separate power amplifiers based on them. The first of these -- in fact, the first standalone amp ever from Axiom Audio -- is the A1400-8 multichannel model.

Description

At $3850 USD, the A1400-8 might seem a little out of place in Axiom’s lineup of otherwise moderately priced products. But as Colquhoun points out, there are plenty of good $1500 multichannel amps already on the market that offer respectable performance. With the A1400-8, he’s developed what he considers to be a reference powerhouse that can easily drive Axiom’s largest speakers, such as the M80 v2 -- or speakers made by anyone else -- to home-theater-approved volume levels.

As is becoming more and more common, the A1400-8 is a switch-mode amplifier. Unlike a traditional class-A or class-A/B linear design -- in which a complementary pair of output devices is biased so that both are never off at the same time -- a switching amp’s output devices switch on and off. This makes switching amplifiers far more efficient in operation; they typically approach 90% efficiency, vs. about 50% for class-A/B designs.

Not only is the A1400-8 efficient, but Axiom claims that it’s immune to output-device clipping, which causes excessive distortion. This is because its output devices are rated to handle more power than the power supply can provide. To achieve this, Axiom uses extremely robust, custom-designed MOSFETs as output devices. A massive toroidal transformer and four huge capacitors with a total of 140,000µF of capacitance supply the power. The A1400-8 is rated to deliver a maximum of 1400W of continuous power into any combination of channels. For example, Axiom rates it at 200Wx7 into all impedances, or 350Wx1 into 8 ohms, or a whopping 1200Wx1 into 2 ohms -- all without any output-device clipping.

Although it weighs a hefty 54 pounds, at only 18"W x 4"H x 17.5"D the A1400-8 is, like most switching amps, deceptively small, considering that it’s a relatively high-powered eight-channel design. Those eight channels mean that the rear panel is crowded with outputs and inputs; the former are standard heavy-duty binding posts, and the latter can accommodate XLR connectors, professional 1/4" phone plugs, or RCAs (with the provided adapters). There’s also a rocker switch for mains power, and a 12V trigger. A peculiarity is that the AC power inlet is on the A1400-8’s bottom plate. This means that a heavy-duty, aftermarket power cord is out of the question, unless there’s an opening in the shelf under the amplifier to feed the cord through, or you can find a cord with a right-angle connector. On the gently curved front panel, available in silver, black, or champagne, are only a raised Axiom logo, an On/Off pushbutton, and a blue indicator light.

Performance

In the time I had the A1400-8 in my system, I never really noticed its sound. That’s a good thing. Like other high-quality solid-state amps I’ve had here, the A1400-8 was exceedingly neutral, with a dynamic quality that sounded as good with two-channel music as with multichannel film soundtracks.

With movies, the A1400-8 would play as loud as I could bear while maintaining its composure throughout the frequency range. When I cranked up The Replacement Killers (Extended Cut) on Blu-ray, the uncompressed PCM soundtrack was underpinned by cleanly reproduced deep bass. Although the subwoofer generally handles much of the low frequencies in a movie soundtrack, the bass coming from the other speakers was incredibly tight and well defined. This made the overall sound more coherent and better integrated throughout the low end. In the opening credits, the pounding electronica of Crystal Method’s "Keep Hope Alive" exhibited very little boom, remaining clearly delineated from the barrage of gunfire and other chaotic sound effects.

While there was no question that the A1400-8 could easily reproduce the most deafening sound effects in movie soundtracks, it also got all the little details right. Explosions and automatic-weapon fire surrounded me as I watched Black Hawk Down, but I was still able to make out, as never before, the sounds of dropped shell casings, the crunch of soil under boot soles, the rustling of uniforms among the mayhem. Even the tiniest audible cue -- such as the prolonged, shimmering decay of a sword being sheathed in Kill Bill: Vol.1 -- was not glossed over.

As powerfully impressive as the A1400-8 was with movie soundtracks, it wasn’t until I played a multichannel music disc that I truly appreciated what it was capable of. Playing back a live concert recording while maintaining realistic volume levels can be far more difficult than reproducing an action movie’s occasional car crash or explosion. With Shakira: Oral Fixation Tour on Blu-ray, I could figuratively turn my system up to 11. Not only was the bass loud, but the drums and bongos hit me as hard and fast as punches to the chest. Wyclef Jean’s rapid-fire rap on "Hips Don’t Lie" was well articulated and mostly intelligible. Most important, Shakira’s evocative vocals didn’t become screechy or harsh, even at less-than-sane volume levels. I did hear some slight compression at incredibly high volumes, but then again, I’d never heard my system play so loud with so little distortion.

Nor did the A1400-8 falter when playing back two-channel sources. The sound was just as powerful and captivating with music CDs as with movie soundtracks. Eva Cassidy’s Live at Blues Alley [CD, Blix Street G2-10046] is not the most pristine recording ever made, but it’s long been one of my references for its intimate portrayal of a live club performance. The Axiom vividly reproduced Cassidy’s voice without making it sound too forward or up front, which gave it a surprising sense of realism. I enjoyed her moving rendition of "People Get Ready," probably my favorite track on the disc, but was also thrilled by how "Fields of Gold" really came alive. Her voice was sultry but vibrant and placed precisely between the two main speakers, the sounds of guitars floating perfectly behind them.

Comparison

My main speakers are typically driven by a pair of Bel Canto e.One REF1000 monoblocks ($3990/pair), which are rated at 500Wpc into 8 ohms or 1000Wpc into 4 ohms; and my center and surround speakers by a Bel Canto eVo6 ($4290, discontinued), rated at 360Wpc into 8 ohms, in bridged-mono mode. The powerful and dynamic Axiom A1400-8 easily out-muscled the eVo6, and its big, open sound challenged even the e.One REF1000s.

But the A1400-8 wasn’t only about volume -- the soundstage on Madonna’s Ray of Light [CD, Warner Bros. 093624684725] had greater height and extended slightly farther past the speakers’ outer edges. Instruments within that soundstage had more precise placements, and the imaging was eerily holographic. Compared to the Axiom, vocals sounded a bit recessed through the Bel Cantos. This gave the Bel Cantos a more intimate presentation that some will prefer, but through the Axiom, voices were more in the plane of the speakers and better balanced overall.

The Bel Cantos were better able to flesh out recordings with a fuller sound than the somewhat leaner but more transparent Axiom. On "Grave Digger," from Dave Matthews and Tim Reynolds’ Live at Radio City Music Hall (Blu-ray), the voices sounded more open with the Axiom, but the guitars sounded bigger and bolder with the Bel Cantos. I could go on about the relative merits of the A1400-8 and my Bel Cantos, but here’s the bottom line: At less than half the price, the Axiom was a worthy alternative to my surround system’s reference amps.

Conclusion

I’m not sure if, as Axiom claims, the A1400-8 is immune from output-device clipping, but it could play extremely loudly with little apparent distortion. Not only was it amazingly powerful, but its transparent, open sound was immediately involving, and didn’t lose its appeal over the long term. Although I thoroughly enjoy the sound of my more expensive array of Bel Canto amplifiers, I could easily live with the Axiom as the sole source of power for my reference system. Considering both the quality and quantity of sound that the Axiom A1400-8 provides for $3850, it’s one heck of a bargain.

Manufacturer contact information:

Axiom Audio
2885 Highway 60
Dwight, Ontario P0A 1H0
Canada
Phone: (866) 244-8796, (705) 635-3090
Fax: (705) 635-1972

E-mail: info@axiomaudio.com
Website: www.axiomaudio.com 

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