Conversation so far:
What was the Kinks' musical style?
The Kinks started out playing the then popular R&B and blues styles; then developed louder rock and hard rock sounds — often labelled as the original punks.“
What was the Kinks' favorite style to perform
Dave Davies was really bored with this guitar sound – or lack of an interesting sound so he purchased a little green amplifier ... an Elpico and twiddled around with it.“

Question: What did the green amplifier do?
Self-contained rewrite: What did Dave Davies' green amplifier do?