AV Receiver Reviews

Performance

There’s a certain class of audio-reviewer statement that I’m extremely leery of, and here comes one: Everything I listened to via the 751R, from the CBS Evening News to big-budget Blu-rays, sounded great, with a subtly relaxed clarity that my ears found addictive.

Can I quantify this? No. Did I perform level-matched A/B comparisons with other receivers, double- or at least single-blind? No. (Such comparisons are wholly impractical, at least in my studio.) Do I have one shred of hard evidence that Cambridge’s receiver is in any technical sense “better” than some other receiver or amplifier? No. Does it have anything at all to do with Cambridge’s massively DSP’d upsampling audio technologies? I have no idea.

Such are the hazards of audio criticism. What I can say (or repeat) is that the 751R sounded lovely every time I switched it on. Two-channel recordings like old friend Bonnie Raitt’s latest, Slipstream (on an 88.1/24 high-rez download from HDtracks.com — and yes, I pay for these), produced the kind of distinct, detailed timbres and “open-weave” sonic textures I expect from my stand-mount 2-way monitors, when they’re doing their best work with the best recordings. Raitt’s version of Bob Dylan’s “Standing in the Doorway” (late Dylan, from 1997’s Time Out of Mind) features a deceptively simple texture built up of heavy, deep bass, a very loose kick drum, languorous pedal-steel, Bonnie’s own peerless legato slide playing, and delicate snare brushwork. Yet every element was distinctly present, and easily teased out by the ear, if it chose. Mine found the brushed snare and deep drum to be particularly convincing, and Raitt’s hard-used but still-liquid voice was reproduced with impressive finesse.

Moving on to cinema sound, I elected to go big from the start with a shiny new Blu-ray of The Hobbit: An Unexpected Journey. I just can’t get enough of those lovable Halflings, though I found the movie to be noisy, repetitive, long, and generally tiresome. Nonetheless, it provides yet another reference-grade soundtrack from the Peter Jackson blockbuster mills, and the Cambridge was ready and eager to display it to full effect.

And I do mean “effect”: The 751R easily delivered the loudest scenes with full impact at true-cinema levels, even while retaining all the detail and easy openness I’d noted on music. The Cambridge’s surround palette is limited to the complete Dolby and DTS menus for multichannel and encoded signals; no “Thrill Theater” or “Disco” settings here. But this includes Dolby PLIIz processing with its height channels, and these couldn’t ask for a better demo than The Hobbit’s chase through the Orc mines (Chapter 27, on a set apparently borrowed from Indiana Jones and the Temple of Doom), where they added dramatically to the many vertiginous vertical effects.

Cambridge incorporates full video processing and scaling in the 751R. This aced my usual rotation of scenes and test patterns, upconverting (up to 1080p) and transcoding from composite-, component-, and S-video sources without incident. (This is hardly surprising, since Cambridge employs Anchor Bay’s ABT2010 chip for the number-crunching, an upgrade from the Azur 551R receiver’s Faroudja DSP, itself a solid performer. The same chip has appeared in numerous well-regarded video components from Oppo Digital and others.) You can choose to bypass or process individually by input, and set the usual video parameters (such as contrast, detail, and so on) for processed ones. The 751R has no provision for 4K video upconversion — something that the Asian makers’ flagships mostly now do.

Ergonomics

Cambridge’s marketing materials make it clear that the Azur line is about sound (and video) quality, not features. That’s fine: In day-to-day use, the 751R is a turn-it-on-and-forget-it pleasure that will regularly demonstrate the truth of this claim.

Nevertheless, for almost everything I loved about the 751R’s sound (and vision) usability-wise, I could find something I felt ambivalent about. The onscreen menus for setup and calibration are plain, clear, and easily followed text — but there are none for in-line use, not even any pop-ups to display helpful info like volume, listening-mode, or mute changes, nor channel-level adjustments, signal-format, or any other data.

Such onscreen aids are non-essential (if convenient — I’ve come to depend on them), as all this stuff appears on the front-panel display. But that low-contrast (though sexy) blue-on-black affair proved difficult or impossible to decipher from my listening chair about 11 feet distant, even when I was wearing my new, blisteringly expensive, computer-optimized progressive-lens specs.

Speaking of channel-level adjustments, making any such changes on the 751R is a project: There’s no provision to do so anywhere other than the main speaker-setup menu page, a 30-second round trip, and the opaque menu obscures the whole TV screen, though sound remains active.

And speaking of the remote, while it’s a very handsomely crafted brushed-aluminum item, its ergonomics are less lovely. There’s no key illumination, the buttons are small, and their labels are smaller, such that in dim light I struggled to read them even with my new glasses. (C’mon, who buys a $2,700 A/V receiver? Middle-aged, successful men, that’s who. And how many Just for Men users without reading glasses do you know?)

As mentioned, there’s no facility for streaming content, though the 751R does have an asynchronous USB port for playing up to 192/24-rez computer audio files, with the receiver acting as an outboard DAC/amplifier. In that case, however, you have to select the content and control its playback from your computer.

Sure, you probably already have streaming via your Blu-ray player or set-top box. But the 751R’s competition mostly now includes wired or even wireless onboard streaming at one-third the price or even less. There’s no Bluetooth, either — no great loss in my book if you value sound quality, which doubtless was Cambridge’s conclusion, too. Cambridge does provide Apple iDevice connectivity, but only through an optional hardware dock. You get basic control via the 751R’s remote, though you first have to go through a rather Byzantine remote-“pairing” process.

Like virtually all A/V receivers today, Cambridge’s flagship incorporates source-independent second-zone routing of stereo audio, along with composite-/S-video. However, the 751R adds a component-video output for second-zone HD potential, as well as a dedicated subwoofer output for 2.1-channel audio; you can even select a stereo-downmix signal from a digital/HDMI source. The 751R’s IR-repeater and 12-volt-trigger facilities are also unusually flexible, and the receiver comes with a card-style, dedicated, second-zone remote, a very welcome convenience.