Music produced by equipment has trans­formed because its ear­ly 20th-cen­tu­ry start­nings from obscure avant-garde exper­i­ments to mas­sive­ly pop­u­lar gen­res of glob­al dance and pop. This Professional­lif­er­a­tion, notes Ishkur—designer of Ishkur’s Manual to Elec­tron­ic Music—has­n’t constantly been to the good.I