CD : An Optimal Music Media?
music media sources are primarily digital (CD, SACD, HDCD, DVD-A).
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.