n.五极真空管
The LV60 is typically pentode amplifier and is constructed in class AB for ca. 65 Watt power output. 两个机器的不同，从电阻可以看出。发出噪声的，就是更换过电阻的这台。
resistance-coupled pentode amplifier stage 电阻耦合五极管放大级
transistor pentode 晶体管五极管
single diode pentode 单二极五极管
pentode field effect transistor 五极场效应晶体管
