Class A power amplifiers generate a lot of heat. Compared with ordinary power amplifiers, their lifespan will be shorter, but it is difficult to evaluate how many years they can be used. The use environment is also critical. Generally, it will not be a problem for 3-5 years of normal use, and some parts are of good quality. The domestic power amplifiers, especially Class AB, have not broken down even after 15 years of use. The DC211 purchased by Starbucks many years ago is used almost every day, and it has been used for more than 16 years and is still working normally.