8917 ADDITIONAL INFORMATIONOptimum surround sound for different sourcesThere are currently various types of multi-channel signals (signals or formats with more than two channels).2 Types of multi-channel signalsDolby Digital, Dolby Pro Logic, DTS, high definition 3-1 signals (Japan MUSE Hi-Vision audio), DVD-Audio, SACD (Super Audio CD), MPEG multi-channel audio, etc.“Source” here does not refer to the type of signal (format) but the recorded content. Sources can be divided into two major categories.2 Types of sources• Movie audio Signals created to be played in movie theaters. In general sound is recorded to be played in movie theaters equippedwith multiple surround speakers, regardless of the format (Dolby Digital, DTS, etc.).FL CSW FRFL CSW FRSL SRSBSL SRSBMultiple surround speakersMovie theater sound fieldListening room sound fieldIn this case it is important to achieve the same sense ofexpansion as in a movie theater with the surround channels.To do so, in some cases the number of surround speakers isincreased (to four or eight) or speakers with bipolar or dipolarproperties are used.• Other types of audio These signals are designed to recreate a 360° sound field using three to five speakers.In this case the speakers should surround the listener from all sides to create a uniform soundfield from 360°. Ideally the surround speakers should function as “point” sound sources in thesame way as the front speakers.FL CSW FRSL SRThese two types of sources thus have different properties, and different speaker settings, particularly for the surround speakers, are requiredin order to achieve the ideal sound.The AVR-3805 is equipped the function of surround speakers selection that makes it possible to change the settings according to thecombination of surround speakers being used and the surrounding environment in order to achieve the ideal surround sound for all sources.This means that you can connect a pair of bipolar or dipolar surround speakers (mounted on either side of the prime listening position), as wellas a separate pair of direct radiating (monopolar) speakers placed at the rear corners of the listening room.SL: Surround L channelSR: Surround R channelSB: Surround back channel(For 6.1-channel system)