Apparently, Wagner coined this word himself. The British Telegraph parses it as meaning something like “nonsense sound factory tools”. But I think Wagner might have shot himself in the foot here without realizing it. If the sound of an instrument he hated could be so easily captured by the ordinary phonology of German, then what does this say about the phonaesthetic qualities of his mother tongue? More importantly, about the libretti of Wagner’s operas? If pressed, wouldn’t he have to admit that his operas sounded like a chorus of saxophones? :)
Setting aside debate about the beauty or ugliness of the German language, would any of my German-speaking friends care to take a crack at parsing out the individual parts of this remarkable word?
 I picked the word up reading Omniglot blog, but to give a printed source: Slominksy, Nicolas. A Thing or Two About Music. Westport: Greenwood, 1972 [first published, 1948], p. 30.