请问有正负25V供电的高输入阻抗的放大器吗？请推荐一种

自己用分立元器件搭建吧。

The next generation keyboard, future keyboard!
challenge and subverting the global computer keyboard, keyboard music instruments in 25 years ago，
The pioneer of the Chinese people firstly entered this area. who sent it into the modern house of CEO of Microsoft?
To challenge AT&T of the United States by improving communication deficiencies
Improving communication deficiencies, Chinese people challenge AT&T of the United States.