The TX-NR616 doesn't have built-in Wi-Fi, like the competing Sony STR-DN1030, but it does offer a $25 USB Wi-Fi dongle that you can connect on the back panel. (And there's a front-panel USB port, so you're not sacrificing USB connectivity.) It's much better solution than I've seen from other manufacturers, which only offer pricey Wi-Fi accessories or none at all. (There's also always the option of rolling your own Wi-Fi alternative for your home theater.)
No built-in AirPlay: Most receivers in this price range offer built-in AirPlay, making it possible to wirelessly stream audio directly from an iPhone, iPad, or iPod Touch. It's a significant missing feature from the TX-NR616, but it's not essential since you can always add AirPlay later with a $100 Apple TV, which adds much more functionality. And the TX-NR616's very low street price makes it easier to justify buying a second box. If you're not sure whether you should pick a receiver with built-in AirPlay, check out our rundown of the advantages and disadvantages of built-in AirPlay versus buying a separate Apple TV box.
Two-year warranty: The TX-NR616's two-year warranty is standard, and better than the one-year warranty offered on Pioneer's competing receivers. If you're really looking for peace of mind, the Marantz NR1403 and Marantz NR1603 feature three-year warranties.
Despite the Onkyo's warranty, you may want to be choosier at your retailer than you normally would due to the aforementioned mixed user reviews of the TX-NR616. Our sample performed well with the most recent firmware update, but it appears not everyone's unit is problem-free; there's a chance you'll need to return a bum unit.
3D pass-through, audio return channel, standby pass-through: The Onkyo supports all three of these HDMI features (each of which is explained in more detail here), but while they're all useful, you can largely ignore them when making a buying decision, since almost every newer receiver supports them.
iPhone/iPad-friendly USB port: The USB port on the front panel supports iPhones, iPods, and iPads, so you can connect those devices directly using a standard cable and navigate your music collection onscreen. We also had success using the USB port with a standard USB drive filled with music.
Extensive multiroom functionality: The TX-NR616 is clearly the most flexible unit in this price range for multiroom support, with support for powered second-zone, unpowered second-zone, and unpowered third-zone audio. Most buyers won't need all this functionality, but it's there if you want it.
One caveat about Onkyo's multiroom functionality is that this is one instance where you are limited by Onkyo's lack of AirPlay. An AV receiver typically can't access any of its digital inputs (including HDMI and optical audio) in secondary zones, so if you're using a separate Apple TV box, you can only listen to it in the main zone. However, receivers generally can access built-in streaming services, including AirPlay, so if second-zone AirPlay is an important feature, you'll want look at other models with built-in AirPlay.
Other features: The TX-NR616 can upconvert analog video signals to 1080p over its HDMI output, but that feature isn't nearly as important as it used to be, since analog video devices are pretty rare. There's also support for Dolby Pro Logic IIz processing, allowing for "height" channels, but we don't think the minimal sonic benefits are worth the extra effort. The TX-NR616 is THX Select2-certified, but that's not worth factoring into a buying decision, since non-THX certified receivers can sound just as good.
Setup and calibration
The TX-NR616 features Audyssey's 2EQ automatic calibration system. If you want to do the calibration with a minimum of fussing go for Audyssey Quick Start, which uses a single microphone position (in the prime listening location), and the whole operation takes a couple of minutes. If you can invest a little more time go for the Audyssey 2EQ Full Calibration three-mic position setup routine, which should help increase the sweet spot to multiple seating positions.
Checking the results we noted the speaker-to-mic measured distances were accurate; and Audyssey correctly judged all of our speaker sizes as "small," and its sub-to-speaker crossover settings for our Aperion Intimus 4T Hybrid SD reference speaker system were correct. The sound balances for the speakers and subwoofer were in line with what we've heard from many other receivers.
Sound quality evaluations for 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. CNET's sound quality evaluations are strictly subjective, with CNET Blog Network writer and golden ear Steve Guttenberg comparing similarly priced models in an identical listening environment using the same speakers.
We started our listening sessions with a spectacularly good-sounding concert Blu-ray disc, Peter Gabriel's "New Blood: Live in London." The TX-NR616 put us in the concert hall, the drums and basses in "Biko" sounded big, and on other songs the spread of the large orchestra across the front speakers was impressive. The clarity of the sound was excellent.
The "Avatar" Blu-ray was next, and we jumped ahead to the jungle scenes with the battling Hammerhead Titanothere beasts, which have a habit of knocking down trees or anything else in their way. The scene provided a good workout for the TX-NR616, and when we compared it with a Denon AVR-1912 receiver we noted the Onkyo didn't shake the room as much as the Denon did. When the massive animal runs through the jungle the ground shook more when the AVR-1912 was hooked up to our speakers. In the quieter scenes, the AVR-1912 also produced a closer-to-seamless wraparound soundstage, so the sounds of the birds and insects surrounded us more completely with the AVR-1912.
Back on the TX-NR616 we tested the Audyssey Dynamic EQ and Dynamic Volume features, both of which promise to allow the user to play movies with lots of soft-to-loud dynamic range at quiet, late-night volume levels. The processing definitely reduced the dynamics, so the loud sounds didn't blast us out of our seats. The TX-NR616's nicely designed menu system makes it easy to switch Dynamic EQ and Dynamic Volume on and off, so we could readily compare the sound with and without processing. The processed sound was less dynamic, which is good, but also added a lot of bass and dulled the treble detail, so we preferred the sound with Dynamic EQ and Dynamic Volume turned off. Then again, you might like what the processing offers for late nights.
Listening to the TX-NR616 in stereo with Neil Young's "Chrome Dreams II" CD, the sound was big and spacious, although the Denon AVR-1912 had a richer tonal balance, and sounded more dynamically alive than the TX-NR616. That difference was even more obvious when we turned the volume way up.
What about Onkyo's other AV receivers?
Onkyo makes a ton of AV receivers and many of the step-down models are worth considering, if you're focused on value.
For the average buyer, it's hard to argue against the TX-NR414 as the overall best value. The additional features of the other models (7.1 channels, two extra HDMI ports, multiroom functionality) just aren't needed in most situations and $280 is an extremely low price for what the TX-NR414 offers. The TX-NR515 is also a solid option if you want eight HDMI inputs but don't need the extensive multiroom options available on the TX-NR616.
The TX-NR616 may be a better value than many similarly priced receivers, but the step-down models will be good enough for most.
It's hard to argue against the value of the TX-NR616. If you need all the functionality it offers, it's a great deal, although Onkyo's step-down models may be a better fit for many buyers. Our only reservation is Onkyo's mixed record on reliability. Our review sample worked well, but we'll continue to monitor the user reviews to see if problems persist.