▁middle ▁of ▁the ▁ 2 0 th ▁century , ▁following ▁the ▁incorpor ation ▁of ▁electric ▁sound ▁production ▁into ▁compos itional ▁practice . ▁The ▁initial ▁develop ments ▁in ▁electro ac oust ic ▁music ▁composition ▁to ▁fixed ▁media ▁during ▁the ▁ 2 0 th ▁century ▁are ▁associated ▁with ▁the ▁activities ▁of ▁the ▁Gr oupe ▁de ▁Re cher ches ▁Musical es ▁at ▁the ▁OR TF ▁in ▁Paris , ▁the ▁home ▁of ▁musique ▁conc r ète , ▁the ▁ ▁Nord west deutsch er ▁Rund f unk ▁( N W DR ) ▁studio ▁in ▁C ologne , ▁where ▁the ▁focus ▁was ▁on ▁the ▁composition ▁of ▁elektr on ische ▁Musik , ▁and ▁the ▁Columbia - Pr inc eton ▁Electron ic ▁Music ▁Center ▁in ▁New ▁York ▁City , ▁where ▁t ape ▁music , ▁electronic ▁music , ▁and ▁computer ▁music ▁were ▁all ▁expl ored . ▁Pract ical ▁electronic ▁music ▁instruments ▁began ▁to ▁appear ▁in ▁the ▁early ▁ 1 9 0 0 s . ▁ ▁T ape ▁music ▁ ▁T ape ▁music ▁is ▁an ▁integral ▁part ▁of ▁musique ▁conc r ète , ▁util izing ▁pre - record ed ▁fragments , ▁loops , ▁and ▁sample d ▁sounds , ▁alter ing ▁and ▁manip ulating ▁them ▁through ▁techniques ▁such ▁as ▁speed ▁manip ulation ▁. ▁The ▁work ▁of ▁Hal im ▁El - D ab h ▁is ▁perhaps ▁the ▁earliest ▁example ▁of ▁t ape ▁( or , ▁in ▁this ▁case , ▁wire - record ed ) ▁music . ▁El - D ab h ' s ▁The ▁Expression ▁of ▁Z aar , ▁first ▁presented ▁in ▁C airo ,