What does fever grade mean?

Describes the degree to which something is loved enthusiastically.

The word comes from the word "audio enthusiast". The term "audio enthusiast" was first invented by "audio equipment enthusiasts" in Hong Kong. Around the 1950s and 1960s, the power amplifiers at that time were mainly tube amplifiers. Due to the relatively hot weather in Hong Kong, civilian air conditioners were not yet popular at that time. Audio equipment enthusiasts were always full of energy every time they played with the equipment and listened to music. Their heads were sweating profusely, their faces were red, and they were still enjoying it. Over time, they called themselves "audiophiles", and this title was also accepted by everyone and became a common name for "audio equipment enthusiasts". And slowly evolved into a general term to refer to people who have special interests in certain things, such as "car enthusiasts", "photography enthusiasts", etc... Later, there were corresponding ones, such as "audio equipment enthusiasts" Music equipment, speakers, and even records, media, etc. that are liked by people who are high-end, fashion-loving and trendy are all called "audiophile grade". By analogy, things that are liked and recognized by "enthusiasts" can be called "enthusiast-level".