The C-curve is "flat , but with limited
bandwidth, with -3 dB corners of 31.5 Hz
and 8 kHz, respectively.
"
1-4
Dynamic Range
Many recordings boast a dynamic range of 100dB or more but this is meaningless if you are
using your playback system in a typical room. If you are playing a speaker with a high
sensitivity of say 90db/watt/meter, the SPL will be at least 6dB down at a typical listening
distance from the speaker (about 8-10 feet), reduced to 84dB. If you are using 100watts into
this speaker and that it has virtually no power compression ,the output will reach peaks of
104dB. Dynamic range is the sound level from the lowest to the highest. Since a typical
room has noise level at 55dB(C), total dynamic range will be 49dB, about that of a low cost
cassette player in the 1970s.
Reducing the noise floor by isolating external noise from the room by a factor of 10dB will
give you the equivalent of having a 1000 watt amplifier instead of 100 watts. You could
always go for a 1000 watt amp but then you probably wont care for noise after that since you
may end up deaf instead!!
One of the secrets of great sound is to start with a room that has a low noise floor. As a result
you will enjoy music at lower sound levels because your dynamic range has increased, and
your electronics and speakers will be running with far lower distortion levels. (Amplifiers
and speakers tend to play with lower distortion at lower power levels).
Room Acoustics
Rooms tend to have parallel walls and dimensions corresponding to certain frequencies
from the music program. These frequencies tend to be at the lower range of the audio
spectrum and can enhance or diminish those notes being played. To the listener it can make
the bass tones sound
boomy or ill defined. Some audiophiles tend to be concerned about the
transient response of different types of bass loading. Ideally sealed box alignment would
have the most perfect response but all this is again meaningless when the speaker is situated
in a real life situation of a typical listening room. Any kind of speaker loading is lightening
fast when compared to the acoustics of a room.