How about the big five light courage machine?

Great voice! The intensity of harmonic energy used by the amplifier of the big five lamp machine is the second harmonic, the third harmonic and the fourth harmonic, which are arranged from strong to weak until they finally disappear. This arrangement of harmonic energy enhances people's hearing, increases the level of sound quality, and has rich overtones, making the sound more popular. Secondly, even if the power amplifier of the gallbladder machine is sometimes overloaded, the sound of the electronic tube of the gallbladder machine will not deteriorate too much because of its gentle waveform. Therefore, the biggest advantage of gallbladder power amplifier is that the timbre is basically warm and soft, especially the mid-band timbre of the power amplifier.