I want to know the answer to the following question:
What was first proposed in 1979?
All the background I'm provided with is that "Manfred Schroeder was already a well-known and revered figure in the worldwide community of acoustical and electrical engineers, but his paper was not much noticed, since it described negative results due to the particular nature of speech and the linear predictive coding (LPC) gain present in speech.". Is that enough to answer the question?
Answer: no