Power Amplifier Reviews

No matter the dollar amount involved, it happens to everyone: You get locked on to something new, you watch the glowing reviews and awards pile up, and you consider pulling the trigger when either financial reality or conservatism kicks in. You ultimately think, "If only it were a few hundred (or thousand, or hundred thousand) dollars less." Patience usually pays off, though. That's as clear in the A/V world as it is anywhere, especially in the high end. It's only natural that, when a manufacturer rolls out a new design or line, they start with their best foot forward, which usually ends up being the more-expensive foot. However, most manufacturers will eventually give those of you who are limited to lower price brackets—either by choice or necessity—a taste with lower-priced models. With the legitimate companies, the gap in price between models is almost always significantly greater than the gap in performance.

This scenario has played out with Lexicon's new generation of amplifiers, which debuted with the LX Series. You may remember that the LX-7 earned a rave review and a RAVE Award (best high-end amplifier) in these pages. At around $6,000, it wasn't for everyone. Those who found themselves in the "I wish it were a few thousand less" boat regarding the LX-7 didn't have to wait long, as Lexicon has now rolled out the CX Series, including the CX-7. The CX-7 is not simply the LX-7 with a few less watts and a smaller price tag. In terms of performance, build quality, and even aesthetics, though, it's clearly in the same ballpark. At $2,000 less, that should make anyone who balked at the LX-7 on price alone highly curious.

On the features side, the most obvious differences between the CX-7 and LX-7 are power and flexibility with how you use that power. The CX-7 is rated at 140 watts (8 ohms) by seven channels, while the LX-7 puts out 200 watts per channel. There's also no bridging capability on the CX-7, as there is on the LX-7. Still, a well-designed 140 watts per channel is more than enough to power most speaker loads in many rooms. Sure, it's nice to have a little more, but I doubt you'll find that the CX-7 has any power-delivery issues, difficult loads or not. Bridging is also a nice bonus, but it's hardly common outside the top shelf and is a feature that many people end up using a lot less than they think they will—if ever.

Naturally, there are far more similarities than differences between the CX and the LX lines, such as balanced and single-ended inputs, a streamlined output system using four custom transistors per channel, highly effective protection systems, and even a ground-lift switch for each channel that helps eliminate loop interference. Like the LX models, the CX amps are THX Ultra 2–certified, which means that test samples have already been beaten up far more than most of us will ever do to our personal systems. Protection includes a thermal monitor that shuts the channel down if the heat-sink tops 95 degrees Centigrade, voltage and current monitoring to protect the output transistors, DC protection to prevent direct current, and speaker protection to prevent frequencies below 10 hertz from reaching the speakers. Front-panel LEDs give an instant alert when protection is engaged. A trigger input is aboard, as well.

The Lexicon bloodline was immediately apparent with two-channel music. Like almost every other Lexicon piece I've come across, the CX-7 masterfully delivered presence without editorializing or calling attention to itself. Its pairing with Lexicon's MC-8 pre/pro was every bit as harmonious as the pairing of the LX-7 and the MC-12 that I did a while back. Together, the CX-7 and MC-8 virtually disappeared from the soundscape in terms of coloration, but the sound was never sterile. Pink Floyd's "Another Brick in the Wall" from the second Burmester collection and Babatunde Olatunji's "Mother, Give Me Love" from Chesky's Super Audio Collection Volume 1 were both full of warmth and natural musicality, but they were also sharp and tight. The percussion's pinpoint accuracy in both tracks caught my ear first, as the CX-7 took hold of my Energy Veritas 2.4's two smaller woofers and maintained a firm grip without choking them. It was particularly successful in the lower-mid/upper-bass region with these speakers, an area in which many amplifiers have not succeeded. The bass-guitar line from Sonny Boy Williamson's "Bring It on Home" was immediately up to its role of forcefully driving this track's rhythmic foundation, more so than I've heard it do in some time from these speakers. The amp set the stage with a more-forward perspective that brought the 2.4's overall tonal balance into line without overpowering the rest of the presentation in the process.

Multichannel demos of both music and movies only confirmed that the CX-7 would have no problem blowing some doors off, when asked. While it didn't display the same effortless demeanor and seemingly boundless stage that the LX-7 did (even with the densest material at the unhealthiest of volumes), it more than held its own as things got more intense. I went well beyond rational volume levels before the first hints of compression materialized, which were subtle and momentary. I battered this amp for several days with everything from the delicacy of Muddy Waters' Folk Singer SACD to the aural assaults of The Lord of the Rings: The Two Towers and Band of Brothers. It impressed at both ends of the spectrum. Lexicon's knack for uncovering a startling amount of detail from a recording was about as clear here as it is anywhere, and the CX-7 shrugged off most of my attempts to prod it into losing its cool.

On several occasions, I noted this amp's graceful transient attack, as well as its ability to shift dynamic gears quickly and cleanly. Gandalf's fiery descent with the Balrog from chapter 1 of The Two Towers was a prime example of the CX-7's ability to deliver large, forceful transient peaks but quickly collect itself without leaving any of the subtle details or critical directional cues behind. It also did a nice job of holding the line even as the soundtrack becomes choppy and overdriven, such as with the harsh, distorted sound of the rock walls crumbling as the combatants fall. There was no artificial smoothing, just a quick recovery time and a clear ability to maintain composure even when the source temporarily goes awry.

When the dust settles, Lexicon's CX-7 won't simply be known as the LX-7's little brother. It has plenty of power, plenty of design and build quality, and plenty of swagger to forge its own identity in the amplifier arena. I expect it will grab a particular amount of attention in its own mid-level, multichannel price range, where it makes a strong bid to be considered the class of the bracket. Whether you're an LX-7 fan who just wasn't ready to plunk down six grand or you're simply an amplifier buyer in the mid-price range, the CX-7 clearly belongs on your short list.

Highlights

• Smooth, natural sound with movies and music
• Power delivery beyond its ratings
• Balanced inputs