Judit,
It's good that you are asking the question in an engineering context. As stated, your question is too broad for a simple answer, but I suggest that you pose a similar question on one or more of the specialty forums at Audio Asylum (speakers, cables, amps), where it should generate more in depth technical discussion.
It's good that you are asking the question in an engineering context. As stated, your question is too broad for a simple answer, but I suggest that you pose a similar question on one or more of the specialty forums at Audio Asylum (speakers, cables, amps), where it should generate more in depth technical discussion.