Who is Dischord? What does he ‘specialize’ in?

Dischord is a doctor, who specializes in "noise".

"I am KAKOFONOUS A. DISCHORD, DOCTOR OF DISSONANCE," roared the man, and, as he spoke, several small explosions and a grinding crash were heard.

"Well, you might say I'm a specialist," said the doctor. "I specialize in noise—all kinds—from the loudest to the softest, and from the slightly annoying to the terribly unpleasant.