CD : An Optimal Music Media?
Today, the
music media sources are primarily digital (CD, SACD, HDCD, DVD-A). CD material
is bandlimited at 22050 Hz, which is way beyond the hearing capabilities
of most people (at least for single pure tones!). However,
research has shown that this group delay difference is generally inaudible. The
limitation of upper frequency content is unavoidable, but limitation of the low
frequency content is only introduced in order to spare us (and especially the
loudspeakers) from low frequency noise such as wind introduced by movement of
the musicians, pounding footsteps etc. Limitation
of the low frequency content is also done using IIR filters and that is to a
much larger extent problematic, since very large group delay times (msecs)
hereby are introduced. These delays of certain frequencies are often audible,
but unfortunately also unavoidable (if you really need the lower frequency
limitation!!!) Summation:
The digital signal sources are potentially good, provided that the music
material is mixed by a skilled sound engineer. |