[. . . ] · Twin Drive Rectifier DENON's Twin Drive Rectifier design uses two rectifying diodes in parallel to bring out the maximum potential of the large transformer. Since the rectifiers recharge the large block capacitors at low impedance, they are able to supply ample current to reproduce deep basses as well as sudden bursts of sound from percussion or other musical instruments. · Large Aluminum Extruded Heatsink DENON uses large heatsink made of extruded aluminum. [. . . ] Cinema Equalizer The sound from movie sources recorded in Dolby Digital, DTS or other formats emphasizes high-frequency range due to a theater's front speakers being placed behind the movie screen. If this sound is reproduced in the home theater without correction, the high-frequency range is too strong. The AVR-684 features a Cinema Equalizer to correct these high-frequency components so that the sound is clearer and easier to listen to. (For Dolby Digital, Dolby Pro Logic II, Dolby Digital EX and DTS surround modes) Personal Memory Plus, for Easy Operation The AVR-684 includes the Personal Memory Plus function that automatically remembers the surround mode you last used for each program source, so that you do not need to select the mode again for that program. Adjustable Cross-Over Switching The AVR-684 supports subwoofer cross-over switching with a choice of 4 cross-over frequencies: 80, 100, 120 and 150. This lets you more accurately match the performance characteristics of the subwoofer to the main speaker system. NEW MODEL INFORMATION DHT-684XP Digital Optical Output Front Panel Inputs (with Optical Input) Front A/B Speaker Terminals High-grade Speaker Terminals (except speakers B) Frequency Synthesis Tuning · 40-Station AM/FM Random Preset Memory Tuning · Auto Preset Memory Specifications Input/Output Terminals For Every A/V System · Audio Inputs 8 Analog Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CD, TUNER, DVD/VDP, TV/DBS, AUX VCR, CDR/TAPE, V. AUX(FRONT) 6 Analog EXT. FRONT L/R, CENTER, SURROUND L/R, SUBWOOFER 3 Digital (Optical) Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . COAXIAL X 1 · Audio Outputs 1 Analog PRE OUT Terminals. . . . . . . . . . . . . . . . . . . . . VCR, CDR/TAPE 1 Digital (Optical) Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Optical X 1 · Video Inputs 4 Composite Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DVD/VDP, TV/DBS, VCR, V. AUX(FRONT) 3 S-Video Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DVD/VDP, TV/DBS, VCR 2 Component Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DVD/VDP, TV/DBS · Video Outputs 2 Composite Outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VCR, MONITOR 2 S-Video Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [. . . ] 12. 5 kg, 27. 5 lbs *Design and specifications are subject to change without notice. *"Dolby", "Dolby Digital", "Pro Logic II", and the double-D device are registered trademarks of Dolby Laboratories Licensing Corporation. *DTS is registered trademarks of DTS Technology. DENON ELECTRONICS (USA) INC. [. . . ]