Surprisingly, more of the gain comes from the preamp than the amplifier itself. The signal level of the mic is susbtantially lower than line level; which is the uniform gain by which all audio devices operate. Home standard is 0.7 Volts and professional standard is 1.4 Volts.
In reality, the preamp (pre-amplifier) is also more important to sound quality than the power amplifier.
In digital systems the waveform is captured in voltage "snapshots" in time. They happen so fast that they sound fluid to the human ear. Taking more of these "snapshots" is like raising the resolution on a screen. It is sharper and more realistic with a vibrance on 24-bit rather than 16-bit. For this reason, all recordings done by E Stew Productions since 2007 have been in 24-bit.
Another aspect of high definition is using that resolution with maximum bit depth. Really, the best record capture is approaching clipping, so don't be afraid to crank up those preamps.