When I sat down for some serious critical analysis of the VSX-LX504 in my secondary home cinema system, my wife and I had just finished watching Stranger Things 3 on Netflix in the main media room, so I took the opportunity to return to the final episode, "Chapter Eight: The Battle of Starcourt" since the aggressive sound mix was still fresh on my mind.
Leaving MCACC off for a bit so I could evaluate the receiver's processing and amplification on its own, I found that the VSX-LX504 delivered more than enough power to render the final battle effectively, but more than that, I was impressed by its handling of the show's eclectic soundtrack. Dialogue was wonderfully intelligible even at ear-blistering volumes, imaging and soundstaging were unimpeachable, and nothing struck me as amiss in terms of audible distortion. The LX504 was also more than up to the task of handling the dynamics of the mix--though, of course, without the benefit of any room correction, the bass was somewhat less than controlled. This room has a pretty egregious mode at my listening position that I can't work around with subwoofer placement alone, so I engaged Advanced MCACC to see how well it would deal with the sound.
As mentioned above, Advanced MCACC allows you to turn on or off MCACC EQ and its Standing Wave Control independently. Turning on the latter, I heard an instantaneous collapsing of the front soundstage, and an overall deadening of the sound. A quick check of the Diagnostic PEQ feature of the AcoustiTools app confirmed what I was hearing: Simply put, Advanced MCACC does way too much attenuation of frequencies above 5,000 Hz, no matter which of its three EQ presets you use. You can also manually set EQ presents, but unfortunately it's a graphic EQ, not parametric, so you have no Q control, and the bands are limited to 63 Hz, 125 Hz, 250 Hz, 1 kHz, 8 kHz, and 16 kHz--not nearly fine enough to make any sort of precise adjustments.
With the MCACC EQ turned off (honestly, it does so little to frequencies below 500 Hz that I was better off without it, since my room is pretty well treated in terms of reflections), I returned to that final episode of Stranger Things 3 again so I could get a handle on what the Standing Wave Control does and how well it does it. Roughly 26 minutes into the episode, there's a pretty aggressive deep-bass rumble that served as a great test for the feature. And indeed, with it turned on, that deep rumble was more controlled, less chaotic, more refined. Not by much. Certainly not as well as you'd get with Audyssey MultEQ XT32 and its companion MultEQ Editor app. But then again, MCACC's standing wave amelioration was better than I've heard from some other proprietary big-box receiver room correction systems.
My advice for potential owners of the LX504 would be to run MCACC with as many listening positions as you need to cover your listening area, turn off the MCACC EQ, leave Standing Wave Control on, and try to use some sort of acoustical treatment to deal with reflections, even if it's something as simple as strategically placed bookshelves or draperies.
These observations held true with pretty much everything I watched: from my old standby dialogue clarity torture tests to newer films like Shazam (4K HDR via Vudu), I found the LX504's decoding to be spot on and its amps more than capable of delivering movie and TV show soundtracks with punch, authority, and utter clarity.
A switch to music left me even more impressed. I ran through a wide gamut of cuts from numerous genres, from symphonic selections (I'm recently re-obsessed with Howard Shore's The Lord Of The Rings: The Return Of The King - The Complete Recordings, a 4-CD/1-Blu-ray box that can keep me entertained for weekends on end) to more rocking favorites. The LX504 delivers it all wonderfully, with more of those impressive dynamics that I spoke of above, along with fantastic imaging and soundstaging, even in stereo mode.
What blew wind up my shorts even harder was its performance with Jimi Hendrix' "Bold as Love," from the original CD release of Axis: Bold as Love from the mid-1980s (still my release rendition of this classic album, despite all the subsequent attempts at remastering and re-releasing). The way the receiver handled the kooky stereo mix for this track left me gobsmacked.
Jimi's ethereal vocals seemed to levitate in the air betwixt my speakers, with his delicate guitar licks leaning hard to the right side of the mix. The soundstage as a whole stretched well beyond the boundaries of my little RSL CG3 bookshelves, and then at around thirty seconds in, with the onset of the first chorus, the ramped-up instrumentation spilled forth into the room, stretching deeper than wide.
To put it simply, the LX504's stereo performance is impressive. Full stop. Not just "for a surround sound receiver," either.
I've already covered a few concerns in the Hookup and Performance sections, but just to recap: I don't like that the VSX-LX504's global crossover settings, since a per-speaker crossover would be vastly preferable; I'm not thrilled with Advanced MCACC, as it does far too much to upper frequencies and not nearly enough to lower ones; and I would really love to see a parametric rather than graphic EQ for tweaking the room correction system.
A couple other things worth noting that may or may not be of concern to potential shoppers: the VSX-LX504's video upscaling isn't on-par with that found in AVRs from other manufacturers. In fact, best I can tell, the only upscaling it offers at all is 1080p-to-4K. And to be frank, I didn't find that any better than the 1080p-to-4K upscaling capabilities of my Vizio P-Series TV. That, combined with the fact that its component input only accepts interlaced video signals, may make it a less than ideal choice for those of you who still have HD displays, watch a lot of 720p or lower-resolution video material, and/or have legacy video components.
Competition and Comparison
Probably the VSX-LX504's most significant competition is Denon's new AVR-X3600H, which sells for a little more ($1,099), but similarly offers nine amplified channels, support for the same audio and video formats, and comparable streaming music capabilities, although the means by which those are accessed is a little different (mostly boiling down to the fact that the Denon relies on HEOS). The Pioneer offers a bit more amplification per channel; the Denon offers 11.2 channels of processing, though, and features dual independent subwoofer outputs. It also has one extra rear-panel HDMI input, HDCP 2.3 instead of 2.2 support, and has better room correction.
Onkyo's TX-RZ840 is a pretty much equivalent offering, with much the same connectivity and functionality, and all of the same big features. Their remotes look virtually identical, their I/O boards look almost the same (with a one fewer IR port and trigger port on the Onkyo), and although the Onkyo's room correction system is ostensibly different (AccuEQ Advance w/ AccuReflex), to the best of my memory the results are pretty much on par.
While Yamaha and Sony both offer receivers in this general price range, both are limited to seven channels of amplification, likely making them less than suitable for someone eyeing a 9.1-channel receiver.
For more in-depth reviews of similar product offerings from other companies, please see our AV Receivers category page.
The AV receiver market is reasonably well stocked with $1,000-ish offerings that are packed with features. Amongst those, though, the Pioneer VSX-LX504 9.2-Channel Network AV Receiver stands out as one of the most feature-packed, with a diverse array of streaming music options and (once the firmware drops) access to Dolby Atmos Height Virtualization, which might be a great stop-gap if you're interested in building a full object-based receiver, but just can't install all of those height channels just yet. And who knows? Once I hear it in action, it may be a good substitute for in-ceiling speakers altogether. That remains to be seen.
What I can definitely say for now is that the VSX-LX504 delivers fantastic sonic performance for the price, along with easy setup and a fantastic remote control. I do wish Pioneer's room correction system was more on-par with Audyssey, and I wish Pioneer would implement per-channel crossover capabilities. But for those of you who eschew room correction altogether and don't have any legacy video devices to worry about, assuming you have a speaker system that can be crossed over at one point, it's a solid pick, to be sure.