good reference for would-be Denon buyers..
The 'Official' 2013 Denon "E Series" / "X Series" AVR Model Owner's Thread & FAQhttp://www.avsforum.com/t/1465528/the-official-2013-denon-e-series-x-series-avr-model-owners-thread-faqWhat the heck is the "E Series" and "X Series"Denon has changed their model naming nomenclature, and the new "E Series" models have effectively replaced the lower level (non CI) models from the Denon consumer level receiver lineup. The E-Series features 2-year warranties, with all but the basic E-200 model including Audyssey MultEQ calibration and an ethernet port for network access.
The "X Series" replaced the higher level (CI) models in Denon's receiver lineup; all of these models feature a 3-year warranty, with more advanced Audyssey calibration (XT in the first three models, and XT32 in the X4000) and expanding featuresets for more flexible custom integration and multizone functionality.
E Series ModelsThe lower level "E Series" models feature basic Audyssey MultEQ calibration and offer 2-year warranties. The E200 should be skipped for any serious home theater setup, as it lacks MultEQ, networking, and has lower build quality.
AVR-1513 >> AVR-E200 ($249 msrp)
AVR-1613 >> AVR-E300 ($399 msrp)
AVR-1913 >> AVR-E400 ($599 msrp)
X-Series ModelsThe "X Series" lineup replaces what was formerly known as the "CI" model lineup. These are distinguished from the lower level "consumer" models with more advanced features making them more suited to custom install setups (the original meaning of the former "CI" designation). In addition to features like RS-232 serial control, more flexible multizone options, and 12v triggers, all of the X Series models utilize more advanced versions of Audyssey MultEQ calibration -- the "XT" version for the X1000, X2000, and X3000, and the most advanced XT32 calibration on the X4000. Additionally, all of the X Series models feature a 3-year manufacturer warranty instead of just 2 years on the E Series... and of course detachable power cords (woot!).
AVR-1713 >> AVR-X1000 ($449 msrp)
AVR-2113CI >> AVR-X2000 ($649 msrp)
AVR-2313CI >> AVR-X3000 ($899 msrp)
AVR-3313CI >> AVR-X4000 ($1,299 msrp)