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The pitch for Pioneer's VSX-823-K ($400 street price) is straightforward: six HDMI inputs, built-in AirPlay, and not much else. That's more HDMI connectivity than the similarly AirPlay-equipped Denon AVR-E300 ($400) offers, and AirPlay gives it an edge against other receivers that offer six HDMI inputs at this price, like the Marantz NR1403 and Onkyo TX-NR525.
Where the VSX-823-K falls short is wireless connectivity. There's no built-in Wi-Fi or Bluetooth and adding those features later is pricey, with Pioneer charging over $100 for each of its accessories. The lack of wireless wouldn't be so glaring if it weren't for the existence of the Sony STR-DN840, which offers Wi-Fi, Bluetooth, and AirPlay for just $50 more. That strikes us as a better deal for most buyers, but if you're not tempted by Wi-Fi or Bluetooth, the Pioneer's solid blend of Apple-friendly features and above-average sound quality is worth considering.
Design: Black and boxy
The VSX-823-K isn't breaking any new ground when it comes to design; it looks like every other big, bulky AV receiver on the market. The two large knobs (one for volume, one for input selection) give it a symmetrical feel, and like most receivers it has quite a few front-panel buttons you'll probably never use. For our tastes, the VSX-823-K is just middling in looks, but anyone searching for something nicer-looking should consider the Marantz NR1403 or a compact integrated amplifier.
Nearly all AV receiver remotes are bad, and the VSX-823-K's clicker doesn't rise above that reputation. It gets some things right, like the large white buttons for volume, but it's also brimming with unnecessary buttons and confusing secondary functions that require a pressing the Shift key. If you're investing this much in your home theater, do yourself a favor and get a universal remote.
Features: AirPlay, six HDMI inputs, but no wireless
The VSX-823-K has a solid mix of features for its price.
Its six HDMI inputs are one more input than you get on the similarly priced Yamaha RX-V475 and Denon AVR-E300. One of the inputs is also MHL-compatible, so it will work with devices like the Roku Streaming Stick, although the input's front-panel location means the stick will be hanging off the front. Other legacy connections are surprisingly few -- no component video ports at all! -- but that should be fine for most buyers, with the vast majority of devices using HDMI these days.
Networking features are included, although you'll need a wired Ethernet connection to take advantage of them. AirPlay is the marquee feature for Apple fans, letting you wirelessly stream audio from iOS devices and iTunes. (There's also support for HTC Connect, although we didn't test that functionality.) The VSX-823-K is relatively light on integrated streaming audio services, supporting only Pandora, Internet radio, and DLNA.
The real weakness of the VSX-823-K is in the area of wireless features. It doesn't have integrated Wi-Fi or Bluetooth, and Pioneer's accessories are unreasonably expensive; $130 for Wi-Fi and $100 for Bluetooth. Those prices seem even less defensible when the $450 Sony STR-DN840 offers both built-in Bluetooth and Wi-Fi (not to mention AirPlay, too) for just a little more. If you want wireless capabilities, which would make sense if your music collection revolves around a smartphone or tablet, you'd be wise to check out the STR-DN840.
The rest of the features are less important for mainstream buyers. The VSX-823-K is "only" a 5.1-channel receiver, but most buyers won't need the extra functionality that a seven-channel receiver makes possible: surround back channels, powered second-zone audio, and Dolby Pro Logic IIz "height" channels. There's no analog video upconversion, but again, that's less of a concern now that most modern devices use HDMI.
Finally, Pioneer offers only a 1-year warranty with the VSX-823-K, which is a year shorter than most companies offer. We haven't seen any reports of widespread quality control issues with Pioneer receivers, but it's annoying that the company doesn't offer longer support for products intended to last for five years or more.
If you're looking for more-detailed feature comparisons, check out our giant AV receiver spreadsheet, which compares the VSX-823-K with other 2013 models as we review them.
Setup: Fast and (mostly) accurate
Just like every other Pioneer receiver we've tested, the VSX-823-K features the company's proprietary MCACC (Multi Channel Acoustic Calibration) automatic speaker calibration system. Unlike the Audyssey system featured in Onkyo and Denon receivers that asks the user to move the mic to multiple room positions, MCACC gets the job done with one position, taking just 2 minutes to complete, while offering results that are just as accurate.
Which is to say, no automatic calibration setup program is 100 percent accurate. MCACC identified the size of our Aperion Intimus 4T towers as "large" speakers. They are towers, but their dual 4-inch woofers don't generate the deepest bass frequencies. In any case the VSX-823's sound quality was excellent, so we didn't feel a need to change any of the settings.
This Pioneer's bass management options are more limited than some receivers': it applies the same subwoofer-to-speaker crossover frequency to all "small" speakers, and in this case that frequency was 100Hz for the center and surround speakers. Denon's Audyssey bass management is more flexible and can assign different crossover frequencies to the front-, center-, and surround-channel speakers to compensate for various sizes of speakers and their bass capabilities. While that might make a difference in theory, the VSX-823's speaker-subwoofer blend wasn't an issue, and the sound quality was very good.
Sound quality: Powerful, clear sound
Sound-quality evaluations of AV receivers (and other amplifiers) are controversial. Some say all AV receivers sound the same, others disagree, and we're not likely to settle that argument anytime soon.
What we can say is that AV receiver sound quality has much, much less effect on overall sound quality than speakers or room acoustics, so you're better off spending your home theater budget there. CNET's sound quality evaluations are strictly subjective, with resident golden ear Steve Guttenberg comparing similarly priced models in an identical listening environment using the same speakers.
The VSX-823-K sounded remarkably well-balanced with all of the movies and music we played. The front and surround speakers together created a coherent sound field in the CNET listening room. Soundstage depth was good, so the sound would, depending on the mix, appear behind the plane of the speakers. Home theater muscle was impressive, so the wide-ranging power dynamics required by the rampaging Hammerhead Titanotheres in "Avatar" packed a wallop.
While listening to jazz singer Patricia Barber's superb "Modern Cool" high-resolution audio Blu-ray we heard more texture and growl from the acoustic bass strings than we did with the Denon AVR-E400. The clarity of the percussion instruments was also better on the VSX-823-K. The differences weren't huge, but the Denon's richer but less detailed sound signature was apparent. We also felt the VSX-823-K sounded better when played really loud.
The VSX-823-K's Midnight Mode compression didn't have much effect when we switched it on and off; abrupt soft-to-loud volume changes were still there. Audyssey's Dynamic Volume processing on the Denon AVR-E400 did a better job of maintaining a consistent volume level for late-night listening sessions. Two-channel music on CD sounded big and spacious coming from just the Aperion 4T tower speakers and the Hsu Research VTF-1 subwoofer.
What are the alternatives?
The strongest alternative to the VSX-823-K is the Sony STR-DN840. It packs the same six HDMI inputs, plus it adds lots of wireless functionality, including built-in Wi-Fi, Bluetooth, and AirPlay. That's worth the extra $50 to us, especially with Pioneer's own wireless accessories costing so much.
The Marantz NR1403 is also worth considering at this price. It eschews networking features entirely, but it looks better and still sports six HDMI inputs. Plus, you can always add on the networking functionality you want later with, say, an Apple TV, which is arguably the smarter move.
Finally, it's worth considering whether you even need an full-fledged AV receiver in the first place. If you're willing to downsize your home audio system to stereo, you might be able to use a compact integrated amplifier. They sound great, take up a lot less room, and can make your home theater much simpler.
Conclusion: For AirPlay fans that don't need Wi-Fi
The VSX-823-K isn't our first choice for a midrange AV receiver, but it does stand out by offering more HDMI connectivity and AirPlay than other receivers at this price.