In the field of a so-called audio system, the recent advent of digital acoustic equipment such as CD players and MD players has made it possible to appreciate music and the like recorded on CDs and MDs by reproducing high-speed signals having a broad dynamic range.
In this case, the influence of vibrations of casings, circuit components and the like of the acoustic equipment, such as amplifiers and speakers, of the audio system is an important matter if these pieces of music are to be reproduced with the finest and richest possible musical expression.
This problem is encountered not only in music appreciation using a full-scale audio system but also in music appreciation using a compact stereo system or a radio-cassette player.
In addition, the vibrations of the acoustic equipment also have an adverse effect on the quality of sound outputted from electronic music instruments and such or recorded on a CD or MD at a recording site.
It has been a conventional practice to use a vibration insulator, such as formed of rubber or lead, for absorbing vibrations (reducing noises) in order that the influence of the vibrations of the acoustic equipment may be reduced as much as possible during the musical reproduction or recording (see, for example, Patent Document 1).
Patent Document 1: Japanese Unexamined Patent Publication No. 2000-138988 (Paragraphs [0008], [0019]; FIG. 1, FIG. 3).