Upgrading from Denon AVR 3300

I had previously owned the Denon AVR-3100 which is basically the same as your unit other then the 3300 has DTS decoding. I upgraded to the Denon 2809 and 3808 and can tell you the difference is huge. The biggest thing you are gaining by going to the AVR-1713 is Audyssey EQXT room correction that makes an amazing difference in sound quality. You also get Dynamic Volume and EQ. The difference will be night and day. I went with the 2809 and 3808 because I needed a lot of the legacy inputs that are not found on the newer models like S-Video for my Laserdisc player and phono input as well as a full set of Pre-Outs to run separate amps and since I have an Oppo 103 Blu Ray player with dual HDMI outs I can still do 3D. If I did not have these unique requirements I wouldn't hesitate to look at the 1713. I noticed that Denon has a price reduction on the 1913 right now if some of the other features are of interest. Good luck.

Other than the fact that the 3300 has more power (140W vs. 80W on the 1713), the addition of Audyssey (as noted above) will be a big improvement. There are current 4 versions of Audyssey (2EQ, MultEQ, MultEQ XT, and MultEQ XT32) with the 1713 and the higher Denon "CI" models featuring the XT version while the 616 only features the lowest version of 2EQ which cannot EQ the subwoofer. Go with Onkyo for features and Denon for better audio fidelity whichever is your preference.