On the audio front, you get four digital audio inputs--one coaxial and three optical--but no digital outputs, which is small bummer. The 7.1-channel analog inputs will be very useful when hooking up Blu-ray, HD-DVD, or SACD/DVD-Audio players, and there's also two pairs of stereo analog audio-only inputs--one with a Tape Out loop for recorders. You'll use the subwoofer output jack to connect a powered sub, and the unit's high-quality speaker binding posts accept bare wire ends or banana plugs. If you're connecting an extra set of stereo speakers that live in another room, it's worth noting that the B speakers' spring-clip connectors work only with bare wire ends. And lastly, if you're interested in a more integrated iPod solution, Onkyo's nifty but somewhat expensive DS-A1 ($100) iPod dock connects to the RI (remote interactive) jack.
As mentioned above, the TX-SR574 is a worthwhile upgrade if only to get the component video conversion feature that's lacking on the SR504. Stepping down the Onkyo line will get you the company's entry-level 2006 model, the TX-SR304. That 5.1-channel model offers a bit less power and lacks the 504's XM satellite radio functionality and S-Video inputs but retains the step-up receiver's three component video inputs, despite costing $100 less.
Onkyo 2006 A/V receivers compared:
(These models will remain current through the first two quarters of 2007.)
|Onkyo TX-SR304||Onkyo's entry-level 5.1-channel A/V receiver offers component video switching between three inputs.|
|Onkyo TX-SR504||The step-up to the TX-SR304 is a 7.1-channel model that adds more power, more A/V inputs, and XM satellite radio capability.|
|Onkyo TX-SR574||The TX-SR574 improves on the SR504 by adding the ability to convert any composite or S-Video input to component-video output.|
|Onkyo TX-SR604||Replacing the earlier TX-SR603X, the SR604 is Onkyo's most affordable receiver to offer Audyssey auto speaker calibration and HDMI switching between two sources.|
|Onkyo TX-SR674||One-upping the HDMI switching on the SR604, the Onkyo TX-SR674 adds the ability to convert analog video sources (composite, S-Video, component) to HDMI.|
|Onkyo TX-SR703||A 2005 holdover, the TX-SR703 is THX Select2 certified, but it offers no HDMI connectivity and lacks support for the latest XM surround formats.|
|Onkyo TX-SR803||Also a holdover from the 2005 line, the TX-SR803 improves upon the SR703 by adding support for two HDMI sources but lacks the TX-SR674's ability to convert analog video to HDMI output.|
|Onkyo TX-NR1000||Onkyo's flagship receiver, released in 2005, offers plug-in circuit boards for PC-style upgradeability.|
The TX-SR504 home-theater stamina was fully the equal of any $300 receiver we've reviewed. The 75 watts per channel felt as powerful as most 100-watt models, and it was capable of playing action movie DVDs loud enough to fill a fairly large room. Bass was full and rich sounding, though lacking some of the definition we associate with $500-plus receivers. That extra degree of refinement found in higher-end receivers was also evident when listening to classical music--it just sounded a little harsher than we'd like.
As far as Onkyo's implementation of XM HD Surround goes, it seems to have a performance advantage over other companies' receivers we've tested that also offer the XM-ready feature. The Onkyo's channel separation is superior to the Pioneer VSX-816 ($300) and Yamaha RX-V659 ($550) receivers', but we noted that whenever we were watching DVDs or listening to CDs, we heard a very low-level noise over the speakers (it was only audible only during quietest scenes). An Onkyo rep says the company hasn't been able to duplicate the problem in its tests, but we're not convinced the problem was exclusive to our review sample, since we used the same antenna with the Pioneer VSX-816 and the issue wasn't present. We did manage to eliminate the noise by disconnecting the XM antenna from the back of the TX-SR504, but that's not exactly an acceptable solution. That, paired with the Pioneer's automatic speaker calibration and onscreen display, are the three main reasons the VSX-816 was rated slightly higher.