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.

Additional Resources
• 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 Hookup
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.

Performance
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.