Conversation so far:
was audio frequency amplification something Lee de Forest studied about?
One of de Forest's areas of research at Federal Telegraph was improving the reception of signals.
Are there any other interesting aspects about this article?
July 1913 AT&T, through a third party who disguised his link to the telephone company, purchased the wire rights to seven Audion patents for $50,000.
Did he work alone in his research?
an associate, John Stone Stone.

Question: What kinds of things could be done with audio frequency amplification?
Self-contained rewrite: What kinds of things could Lee de Forest do  with audio frequency amplification?