Household power amplifier can be further divided into the former level of power amplifier, after the level of power amplifier and combined level of power amplifier. A merging machine is a machine that integrates the front and rear stages into one. The prestage is used to initially amplify the signal and adjust the volume; The latter stage is to amplify the signal from the previous stage to push the loudspeaker.
The prestage is also divided into active and passive types. Active precursors use a power source to amplify the signal, while passive precursors only regulate volume. Honestly speaking, today's success of the passive before the level is not much, because the source and after the level of internal resistance is very different, only by a volume switch to the source and after the level connected, the difference between the internal resistance will make the dynamic, details, frequency should be lost! In addition to adjusting the volume of the active pre-level, it can also be used as a buffer at the beginning of the broad and reduce the internal resistance between the sound source and the post-level.
The rear stage is to amplify the signal from the previous stage to the Yang sound device for use, the rear stage must be strong enough to push the speaker. The so-called enough force, does not mean that the louder the more powerful. Must be able to support the big picture of the ensemble without losing its details.
Separating front and rear stages are better than merging machines because each has more room to build more precision. There is also less interference and more detail between the two; Moreover, the separation of front and rear stages will give enthusiasts more options for propulsion.