Brian Kahn is the longest tenured writer on staff at HomeTheaterReview.com. His specialties include everything from speakers to whole-home audio systems to high-end audiophile and home theater gear, as well as room acoustics. By day, Brian is a partner at a West Los Angeles law firm.
The AV preamp has the hardest job of all audio-video components. As the hub and controller of a complex theater and music system it is expected to interact with nearly every component, provide a variety of audio and video processing functions all while being reliable and easy to use. This is no easy feat, especially in today's era of media servers, network and Internet streaming devices. If providing all of these features were not a difficult enough target to hit, keep in mind that it is a moving target. New formats and streaming services are introduced frequently and your AV processor is the component that needs to be able to interact with them.
• Read more AV preamp reviews by HomeTheaterReview.com's staff.
• Find an amplifier to pair with the PR-SC5508 in our Amplifier Review section.
Onkyo takes aim at the full-featured processor target with their newest AV Preamp, the PR-SC5508. This is the most full-featured processor I have ever had in my system. Priced at $2,199, Onkyo has positioned the PS-SC5508 to compete against flagship level receivers and high-performance, high-value processors. While we at HomeTheaterReview.com would never recommend selecting your processor or receiver based upon which unit has the most features, sound modes, etc., it is important that the processor you choose have the features that will enhance your home theater experience, of which the PR-SC5508 has more than I can list here. For starters the PR-SC5508 is a 9.2 channel processor that is THX Ultra2 Plus certified as well as ISF certified. It has eight (yes, eight) HDMI 1.4a inputs with full 3D capability. The PR-SC5508 has an internal HQV Reon-VX video processor as well as the latest Audyssey room correction algorithms, which include MultEQ XT32, DSX, Dynamic EQ and Volume. For the audiophile in you the PR-SC5508 has a built-in phono stage, six Burr-Brown PCM 1795 192kHz/32bit capable DACS for all channels as well as DLNA for network streaming devices and DSD Direct for SACDs. The PR-SC5508 is compatible with all of the latest Internet Radio stations and services, such as Pandora and Rhapsody, and is also iPod ready and controllable via a free Onkyo App available on iTunes.
The PR-SC5508's chassis is full sized measuring eight inches high by 18 inches deep while tipping the scales at a respectable 30 pounds. This is a lot of height considering there are no amplifiers inside. Despite the processor's substantial size it does not look imposing, at least from the front. The front panel is gently sculpted brushed aluminum that has a substantial, well-made feel to it. The panel has a large display across the top half of the unit, flanked on the right by a large volume knob. Underneath the display is a row of source selection buttons and the bottom half of the unit has a drop down door that covers more controls, a USB input, headphone jack and an HDMI equipped auxiliary input.
While I didn't list them above, the PR-SC5508 is capable of decoding all of the new lossless codecs as well as Audyssey DSX and Dolby Pro Logic IIz for new surround channels. While my reference system does not take advantage of these new width or height channels, I did take advantage of the dual subwoofer outputs, a feature I would like to see on more processors. While the processor does not have Bluetooth or Airplay capabilities for iPhone/iPod integration, an iPod/iPhone can be connected through one of two USB ports or the "universal port," which can accommodate a selection of Onkyo branded iPod docks. The ability to bypass your iPod's DACs is significant, especially when your iPod is loaded with lossless audio files. The PR-SC5508 accomplishes this by-passing through the direct USB connection. While I did not have one of the docks to try out this feature I was able to stream lossless audio files off of my Network Attached Storage drive. However, the Onkyo's network streaming capabilities did not include video or photo files.
The multitude of features described above certainly provide the user with a wide variety of media options to choose from but, as we have often said before, being able to access the media is only half the job, the other half involves treating the audio and/or video signals properly. On the audio side of things, the Audyssey processing suite is the newer MultEQ XT32 which sounds, in my opinion, significantly better than the base Audyssey suite. Those who are so inclined can have a professional installer access the MultEQ Pro for further tweaking abilities. The PR-SC5508 has a plethora of other audio processing features too numerous to list here. Onkyo implements the 132 kHz/32 bit Burr-Brown DACs with their proprietary Vector Linear Shaping Circuitry (VLSC) which is said to reduce signal noise. Audio processing is handled by a trio of powerful 32 bit TI DSP chips, which can handle decoding of all the current codecs, equalization, etc. Audio processing can be bypassed in Pure Audio mode which also defeats all display and video circuitry.
Onkyo has long been known for making receivers and processors with extensive and exemplary video processing capabilities and the PR-SC5508 keeps this tradition alive thanks to the internal HQV Reon-VX processor.
Lastly, the PR-SC5508 is THX Ultra2 Plus certified. Although there have been, and for the foreseeable future will be debates among home theater enthusiasts as to the benefits (or harm according to some) of THX processing, the Ultra2 Plus label means that the processor meets a heightened set of standards; unfortunately these standards are not readily available to the public.
The PR-SC5508's relatively large size dominated the shelf I placed it on. At nearly 18 inches deep, the back of the unit extended to the rear of my rack making cable connections a breeze. Connections were made with a variety of Kimber Kables. Sources included an Oppo BDP-83SE and Sony ES DVP-CX777ES. I began my review using my reference Halcro MC-50 amplifier; after getting a good sense of the PR-SC5508's sonic attributes I swapped in Onkyo's PA-MC5500 9 channel, 150 Watt per channel amplifier. The audio signal culminated in my long term MartinLogan reference speakers and the video signal ended with my Marantz VP-11S2 projector coupled with a 100-inch diagonal Stewart Filmscreen StudioTek 100 screen.
After making the requisite connections it was time to fire up the processor and go through the process of assigning inputs, configuring the speakers as well as the audio and video processing. The instruction manual was fairly informative with a decent amount of information about the settings, modes and operation of the processor. However, I found the on-screen graphic user interface to be very informative, easy to use and more attractive than most I have used in the past.
Less than an hour after removing the processor from the box I was sitting in my theater watching some video clips and listening to music. Before you think that is a lot of time, most of it was related to the Audyssey setup during which test tones are played through each speaker and measured from a variety of listening locations throughout the room. The most tedious part of the setup was going through the online streaming setup wherein you have to enter your user names and passwords via a virtual keyboard. This can be a slow process if you have long user names or multiple accounts to enter. Thankfully, it is a one-time event.
Before moving on, I must point out that my initial setup of the video portion of the processor included only the rudimentary video settings. The Onkyo has a plethora of video adjustments for each source and a half dozen picture modes. This allows you not only to tweak the video processing for each source but also for different viewing scenarios. For example if you output the signal for a flat panel for daytime viewing but a projector for nighttime, you're covered. Want something more vibrant for games and sports but more accurate for films? That's covered to. The video adjustments are very extensive and powerful; they go way beyond the video adjustments found on most processors. Users would benefit from having them set by a professional calibrator to achieve the maximum benefit.
I had recently watched Terminator Salvation on Blu-ray (Warner Home Video) with some friends so I put it back in my Oppo and played it through the Onkyo system. Without giving away too much to the few of you who may not have already seen the movie, this post-apocalyptic action flick is full of over-the-top battles and explosions. The Onkyo system had no difficulty properly arraying the sonic images. More importantly, the dialog, including low level dialog among other sonic distractions was easily intelligible. The only thing that jumped out at me as being deficient was the quantity of bass. The Audyssey set levels did not have the same impact as the bass through my Marantz and Anthem systems (Audyssey and ARC settings, respectively). This was easily adjusted by bumping up the LFE channel level 2 dB. On the video side of things, the Onkyo's performance was flawless with no processing artifacts or signal degradation noted. The color saturation remained low as intended by the director rather than being artificially pumped up by the video processor attempting to "normalize" the image.
Read more about the performance of the PR-SC5508 on Page 2.
Wanting to see how the Onkyo's processor would do with a more color
intensive image I played another machine oriented action flick,
Transformers on Blu-ray disc. (Paramount). Transformers is a much more
vibrantly colored film than Terminator Salvation and the Onkyo
processor had no problems reproducing this either. The more vibrant
colors made it easy to see that the moving straight edges and other
shapes were clearly delineated from one another with no jagged edges or
other artifact. This came as no surprise given the Onkyo's ISF certification and HQV processor; of course the fact that the signal was both input and output in 1080p via HDMI.
On both of the above movies, as well as the other 1080p Blu-rays and DirecTV
feeds that I watched through the Onkyo, the handling of the video
signal was exemplary. I am not a professional calibrator, nor did I
have one over during the review process but if I did, I would
definitely take advantage of all of the source and mode memories to
tweak the image for the best possible results regardless of source or
While the Onkyo's video processing is very good, perfect it is not.
I tried watching some DVDs through Oppo at 480i using both component
and HDMI. I set the Onkyo to upscale the signals. When set to 'auto'
the geometry of the image was compressed, however when I set it to
'1080p' or '1080p/24' the image geometry was proper. With the other
image processing settings in their default positions, the image was
soft and the occasional artifact was noticed, even during casual
viewing. Experimenting with the video settings yielded an improvement
but the image was still inferior to the image I obtained when I had the
Oppo perform the scaling. I have no doubt that a professional
calibrator could have squeezed more performance out of the Onkyo than I
but I suspect my efforts and results will mirror those of the users who
forego professional calibration.
Video and movies are only half the story. Music, whether it be stereo
or multi-channel makes up a large percentage of how I spend my time in
my media room. I was encouraged by many aspects of the Onkyo: the beefy
power supply, the inclusion of a phono stage, the ability to handle
high resolution audio files and of course the Audyssey and Dolby audio
processing enhancements. In short, the Onkyo processor did a
respectable job with music but it would not be my choice for stereo
playback. Multi-channel playback was better and competitive with other
processors in its class.
First of all, it was great to listen to high resolution FLAC files
off of my NAS drive with no other equipment and a relatively
straightforward, if rudimentary menu and control system. Peter
Gabriel's album Scratch My Back (B&W Society of Sound, FLAC 48
kHz/24 bit) has been in heavy rotation as well as Elton John and Leon
Russell's The Union (Universal/ HD Tracks, FLAC 96 kHz/ 24 bit). I had
no difficulty discerning the improved sound quality of these files over
their 320 kbps MP3 versions. Soundstages were well formed but were
shallower through the Onkyo than my reference two-channel rig. In
comparing the two systems the Onkyo was a bit thinner in the presence
region and did not resolve as much detail. Most notably the leading
edges of the notes were dulled and the dynamics seemed a bit
constrained. The immediacy of my reference two-channel rig was lost
when playing the same material through the Onkyo system. I can hardly
blame the Onkyo, for the Onkyo processor and amplifier combination cost
about one fifth as much as my reference system.
Listening to Nine Inch Nails' "The Hand That Feeds" from their
concert Blu-ray "Beside You In Time," my impressions of the Onkyo's
music presentation remained the same with the exception of imaging. As
with the Onkyo's movie performance, its sonic imaging with
multi-channel music was quite good. When listening to Orff's Carmina
Burana (Telarc) on SACD via the Onkyo's DSD direct input there was an
increase in resolution and immediacy.
As full featured as the PR-SC5508 is, if I were able to pick and choose my features I would add Netflix
streaming, Bluetooth and Airplay. While we may get some grief for our
criticisms of remotes, they are the primary point of contact with the
theater system. The Onkyo remote is well laid out but a bit crowded and
the back lighting is insufficient as it does not come on until a
function button is pressed and then it does not light the whole remote.
My only criticism from a performance standpoint is that the
processor's music performance, on stereo sources in particular, is not
as good as I would desire in a product at this price point. Video
processing, with the exception of scaling, was excellent. Videophiles
will no doubt have the Onkyo's extensive video controls set by a
professional calibrator, which should minimize this issue.
Lastly, the PR-SC5508 made rather loud clicking sounds any time
sources or sound modes switched. Thankfully the timing of these clicks
usually did not happen in the middle of a movie or listening to a music
disc but they did occur in between tracks streamed from my NAS drive.
Competition and Comparison
The AV preamp market is a rapidly changing one. New features are
incorporated at a startling rate and manufacturers race against each
other to incorporate these features into their newest product lines. If
the Onkyo PR-SC5508 appeals to you but you seek a higher level of
performance you may want to check out the Integra DHC-80.2.
It provides a nearly identical feature set but provides a higher level
of audio performance. While I have not had a chance to use the new Marantz AV-7005, I hear from my colleagues that it sounds comparable to the AV-8003.
I own an AV-8003 and appreciate its improved sound quality. In short,
if your priority is video and multi-channel sound the Onkyo would
probably come out ahead. If sound quality is your concern, especially
two-channel, the scales would tilt back towards the Marantz. For more
on AV preamps in general, check out Home Theater Review's AV Preamplifier section.
Onkyo's PR-SC5508 is well suited to be the
centerpiece of a modern, well connected and networked home theater
system. The Onkyo processor can accept just about any type of audio
signal from just about any conceivable source, from a record player to
high resolution audio file streamed from a computer to the newest
lossless multi-channel codecs. With the other half of the home theater
equation, video, the PR-SC5508 is even more capable. It is ISF
certified video processor, one of the most capable I have seen in an AV
The Onkyo PR-SC5508 processor is very good but it's not perfect. If
you are an iTunes/iPod fan you may miss the ability to stream music via
Bluetooth or Airplay, however, if you don't mind simply docking your
iPod this should not be a problem. If you consider yourself an
audiophile or you plan on listening to a lot of two-channel audio in
your home theater system you should carefully audition the Onkyo before
committing. While the Onkyo's two-channel music performance was merely
adequate, or on par with many of its rivals, its performance on movies
• Read more AV preamp reviews by HomeTheaterReview.com's staff.
• Find an amplifier to pair with the PR-SC5508 in our Amplifier Review section.