Christmas 2007
Christmas is a time when you get homesick - even when you're home
God Bless Our Service People Wherever They May Be!
Record Albums Were Wonderful In The 1950's-1970's
A gramophone record (also known as phonograph record, or simply record) is an analog sound storage medium consisting of a flat disc with an inscribed modulated spiral groove usually starting near the periphery and ending near the center of the disc. When made of vinyl they are also known as vinyl records.
Gramophone records were the primary medium used for commercial music reproduction for most of the 20th century. They replaced the phonograph cylinder as the most popular recording medium in the 1900s, and although they were supplanted in popularity in the late 1980s by digital media, leaving mainstream by 1991, they continue to be manufactured and sold as of 2008[update], still used by DJs and audiophiles for certain types of music, especially electronic dance music, hip hop and heavy metal music.
The normal commercial disc is engraved with two sound-bearing
concentric spiral grooves, one on each side of the disc, running from
the outside edge towards the centre. The last part of the spiral meets
an earlier part to form a circle. The sound is encoded by fine
variations in the edges of the groove that cause a stylus (needle)
placed in it to vibrate at acoustic frequencies when the disc is rotated
at the correct speed. Generally, the outer and inner parts of the groove
bear no intended sound (at least one exception is Split Enz's Mental
Notes).
Since the late 1910s, both sides of the record have been used to carry
the grooves. Occasionally, records were issued in the 1920s with a
recording on only one side. The recording is played back by rotating the
disc clockwise at a constant rotational speed with a stylus (needle)
placed in the groove, converting the vibrations of the stylus into an
electric signal (see magnetic cartridge), and sending this signal
through an amplifier to loudspeakers.
The majority of non–78 rpm records are pressed on black vinyl. The
colouring material used to blacken the transparent PVC plastic mix is
carbon black. Carbon black increases the strength of the disc and
renders it opaque. Polystyrene is often used for 7-inch records.
The sound quality and durability of vinyl records is highly dependent on the quality of the vinyl. During the early 1970s, as a cost-cutting move towards use of lightweight, flexible vinyl pressings, much of the industry adopted a technique of reducing the thickness and quality of vinyl used in mass-market manufacturing, marketed by RCA Victor as the "Dynaflex" (125 g) process, considered inferior by most record collectors. Most vinyl records are pressed on recycled vinyl
