9 Signalling and checking apparatus and instruments; satellite transmission apparatus; global positioning apparatus; navigational apparatus; mobile phones, automotive phones, wireless apparatus and networks; silicon chips (electronic components); application specific integrated circuits; psychoacoustic devices and apparatus using filtering techniques to provide a listener with a more natural sense of space and improved out-of-head localisation of audio signals, acoustic control circuits, acoustic instruments, sound recording apparatus; sound reproducing apparatus; sound receiving head units; computer software