When sound travels from its source to our ears, we automatically sense where it is coming from by analysing and comparing (between left and right ears) three factors: time difference, volume difference and phase difference. These factors are determined by the shape and direction of our head in relation to the sound source. The mathematical function that describes these factors is called HRTF, for Head Related Transfer Function.By using HRTF, it is possible to reproduce the same time, volume and phase characteristics that occur when sound is produced from left, right, centre and surround channels in order to create “virtual” sound sources for each channel, even from two speakers.The technology used to do this is generally called virtual surround. Yamaha 2-Channel True Surround Yamaha has developed new technologies and algorithms that make it possible to achieve 5 and 7-channel surround sound with only two front speakers, and without using wall reflections. Unlike other virtual surround systems,you can actually identify precise sound locations as if there really were speakers for the surround and rear channels. What’s more, the sound is extremely clear, natural and realistic,noticeably superior to that of other systems.
