I’ve been known, after a few beers, to tell a bar full of audiophiles that Class D should be illegal. I’ve loved its power and efficiency, but it has a particular signature that I find alternately fatiguing and annoying. I’ve never much cottoned to the sound. You can generally count on me to find something nasty to say about almost any Class D amp. Giving me a pair of them to review is a wholly perverse notion.
The AURALiC Merak amplifiers are based on uCd amplifier modules from Hypex. Xuanqian Wang also makes no secret that this was decision based on cost engineering. He wanted wide bandwidth performance, high power, and a reasonable price. The Class D uCd was the only way to reach his goals.The uCd alone, though, was wholly unsatisfactory to him. It’s fair to say that I have some sympathy for this position.
AURALiC’s engineering in the $5,000 per pair Merak was aimed squarely at people like me. Each deceptively heavy, LP-sized box has three tricks to defeat the usual challenges with Class D. The first, and the reason the box is so very heavy, is that it’s almost entirely made of power supply. The bulk of the weight comes from a custom-wound toroid power transformer providing an unshakeable foundation to linearize the amp module itself. This is aided and abetted by 56,000uF of capacitance, enough to handle any load.
The second trick is just old school. AURALiC uses a Lundahl transformer on the input. This not only handles the phase splitting, but it breaks ground loops, removes HF grunge, and matches the system gain so that the amp module is operating in its most favorable region.
Lastly, AURLiC bypasses the uCD input stage in favor of one based on the exceptionally linear gain stage of their preamp. This amp is not meant to sound like “Class D.” It’s meant to sound like an AURALiC component. The full design is nothing short of breathtaking, with careful attention to detail wherever you look. This becomes stupidly obvious when you notice the Cardas Patented Binding posts — my favorite — on the back.
The final product is a beautifully crafted, cleanly modern, cool-running box that will fit on the shelf on an Ikea Expedit, suck infinitesimal juice from the wall while idle, deliver 200 watts into 8 ohms, and shove 400 watts of power down the throat of any 4 ohm load.
There are a couple of other points to mention. The first is that the Merak only takes balanced inputs. The second is that if you’re a complete nutbag who needs more than 400 watts of brute grunt, the Merak can be bridged with a partner to Frankenstein up 800 watts per side. In short, that clean, modern design hides a monster.
It’s fair to say that I respect the Meraks more than I love them. There are things about them that make them wholly unsuited to the systems I prefer. I tend to prefer glowing tubes. I tend to prefer high-efficiency speakers. I tend to prefer wholly ridiculous coaxial drivers.
I hauled out a pair of (in for review) E-3 speakers from Endeavor Audio. These are just under 90db sensitive and present a 4ohm load. They’d been an iffy match for my Manley Snappers (which prefer something above 6ohms) since they showed up. The Meraks, which had annoyed all the living crap out of me on my big coaxes, brought the iron fist down on these things. It brought the iron fist down hard.
The iron fist is a very good thing indeed.
Playing at average volumes from the low-70s up to ohmygodturnitfoff, the Meraks did a pretty good impression of actually being my Snappers — not bad for being 2/3 of the price. The tone was basically identical. The speed was basically identical. The dynamic shifts were basically identical. They were, if anything, better at picking apart complexities. Multipart vocals on which the Snappers might dwell a bit too much on the “multi” were better defined the Meraks’s tendency to showcase all the parts. The Snappers held a slight edge in the treble reproduction in all cases (Max Roach’s cymbals will attest to that), but the Meraks’ control of the bass and superlative even-handedness through the vocal range made them far more useful tools. This was by far the most refined presentation that I’d heard from a uCd amplifier.
I’m not even going to mention the almost forty dollars per month that these things knocked off my power bill.
Down at late night listening levels, though, some problems cropped up. The amps were just too mellow, just a little too shy about dynamics. I was starting to get the sense that these amps wanted nothing more than to work for a living.
A couple of years ago, I did a silly thing. I bought a pair of old Martin Logan Quests from Echo Audio in Portland. I’d wanted a pair since I was a kid, and when I saw a pair on the floor, I had to have them. They’ve spent most of the intervening two years unloved in a spare bedroom as a line of wimpier and wimpier tube amps has migrated through the house. I should probably sell them, honestly, but I’ve been too lazy to get around to it. They’re inefficient, they’re a pain to drive, and they’re actively hostile to most amps.
The Meraks, of course, just loved those old Quests. Loved them. Even late night listening levels were just fine, with better-than-good dynamic tracking and all the precision I’d come to expect from listening to the Merak/Endeavor combination. For most of their two months here, I sidelined the coaxes and stuck to either the old Quests or the Endeavor E3.
Whether from my K&K Linestage, the balanced outputs of a TVC, or from the balanced outputs of a Parasound P-3, the Meraks added nothing. No color, no tone, nothing. With three exceptions, they served out whatever got dished up.
First, as with most Class D implementations that I’ve heard, the Merak were sensitive to the conditions on the power line. In my particular case, I shared the grid with a grocery store and the municipal machine shop. Every time the compressors on the giant freezer turned on, or whenever somebody decided to spot weld, the amps responded with a steeliness that was shockingly out of character for them. The good news here is that an Audience aR2 utterly eliminated the impact that these occasionally obnoxious neighbors had. A cheap, surplus isolation transformer was very nearly as effective, and much more affordable. Let’s be honest: a plan to mitigate the issues that arise from suboptimal power is always wise if you want to get the most out of any revealing system. Just because the Meraks’ are so unfussy that it’s easy to forget how superbly revealing they are is no reason not to treat them with the respect you’d give to any other serious piece of equipment.
The second exception is that the amps need to be left on and warmed up. This is not an option. Don’t even try to listen to them when they’re cold. They barely touch the wall-juice when they’re silent, so this isn’t an earth-killing choice. They need days, not hours, to come on song. The single most effective tweak that you can do to these things is leave them alone. They are the opposite of tweaky audiophile bullshit. Plug them in, turn them on, and forget about them.
The third exception is that I never felt that the Meraks on their own matched my tube amps (any of them) for natural treble. They simply didn’t have that basic, happy airiness. Fortunately, there was even a solution for this.
That solution is called the “Taurus Pre.” That solution is so effective that my advice would be to consider the combination of the Taurus Pre and the Meraks to be an integrated package. The system as a whole is so dramatically better than any other pairing I tried with the Meraks that I wouldn’t recommend buying the amps without at least auditioning the Pre.
That glassy glare of the Taurus Pre that had seemed so minimal when I paired it with other amps completely disappeared here. The Meraks removed the last of what I would consider the tonal hallmark of the solid state preamp. Similarly, the Meraks’ treble became significantly more natural when paired with the Taurus Pre.
The sound? In your face precision, precision, and more precision. If image depth suffered a little, the rest of the performance was such an adrenaline rush that I hauled out the 95db sensitive Tannoy Glenairs and queued up everything I had by Georg Solti and the Chicago Symphony Orchestra. I dragged Roches albums out of storage just to hear how the stack layered the sisters’ voices. I even made it through all five discs of Mosaic’s Thad Jones/Mel Lewis “Complete Solid State Recordings.” When the clock hit 4:00 am, I finally turned the volume down.
I really shouldn’t have done that. Coasting along in the milliwatt range isn’t their forte. The Meraks definitely want to work for a living.
If you’re into high-efficiency speakers and whisper quiet, late night or background listening, these probably aren’t the amps for you. If you have reasonable speakers and like to pay attention when you listen at more realistic volumes, you may be very interested indeed. Something in the 83db to 89 db sensitive range would seem just about ideal, allowing you to listen at reasonable and somewhat lower-than-reasonable volumes without sacrificing dynamics, while still having more than enough decisive grunt to let you listen at wholly unreasonable volumes when the need arises.
AURALiC has made some great looking, well-built, energy-efficient boxes that offer a clean and precise sound without even a whiff of tweaky audiophile bullshit. It’s hard to walk away from that with anything other than respect and enthusiasm.
I honestly can’t wait to see what this company does next.