Hi Richardmr,
Drums are one of the most difficult instruments to mike, record and reproduce either through a live sound system or home audio system.
Drums and cymbals are able to produce very high energy SPL waves. The nature of the wave is that there is an intense leading edge transient to the waveform coupled with a complex harmonic structure. These waves tend to reflect off of the room surfaces quite energetically. Close microphone technique is usually the norm and trying to capture natural reverberation without coloration requires tremendous skill. Most microphones overload with the initial transient and there are tradeoffs in the design of microphones that are robust enough to handle the task.
Additionally, the recording system has to cope with these trasients and waveforms - some accomplish this more successfully than others. Mixing the the drums "down" relieves the recording and playback system of stress.
I have been a professional drummer for over thirty years and have played with everything from hard rock, pop, folk, country, light jazz, ethnic and totally acoustic music ensembles. Depending on the choice of drums, drum heads, sticks, brushes and technique, a drummer can vary the intensity from barely a whisper to deafening levels. Microphones, mixing boards, recording sytems, amplification, speakers and producer's sensibilities can rarely keep up.
Best Regards,
Barry Kohan