Here is a reply I made to one of my friends (also a customer) concerning CD quality. He, like me, agrees that CDs sound better than streamers. Call us dinosaurs. That is our story and we're sticking to it! He is getting a new DAC and other goodies and I just built him an HDMI cable to try.
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From Wiki -
"CD molding machines are specifically designed high temperature polycarbonate injection molders. They have an average throughput of 550-900 discs per hour, per molding line. Clear polycarbonate pellets are first dried at around 130 degrees Celsius for three hours (nominal; this depends on which optical grade resin is in use) and are fed via vacuum transport into one end of the injection molder's barrel (i.e., the feed throat) and are moved to the injection chamber via a large screw inside the barrel. The barrel, wrapped with heater bands ranging in temperature from ca 210 to 320 degrees Celsius melts the polycarbonate. When the mold is closed the screw moves forward to inject molten plastic into the mold cavity. When the mould is full, cool water running through mold halves, outside the cavity, cools the plastic so it somewhat solidifies. The entire process from the mould closing, injection and opening again takes approximately 3 to 5 seconds.
The molded "disc" (referred to as a 'green' disc, lacking final processing) is removed from the mold by vacuum handling; high-speed robot arms with vacuum suction caps. They are moved onto the finishing line infeed conveyor, or cooling station, in preparation for metallization. At this point the discs are clear and contain all the digital information desired; however, they cannot be played because there is no reflective layer.
The discs pass, one at a time, into the metallizer, a small chamber at approximately 10−3 Torr (130 mPa) vacuum. The process is called 'sputtering'. The metallizer contains a metal "target" – almost always an alloy of (mostly) aluminum and small amounts of other metals. There is a load-lock system (similar to an airlock) so the process chamber can be kept at high vacuum as the discs are exchanged. When the disc is rotated into the processing position by a swivel arm in the vacuum chamber, a small dose of argon gas is injected into the process chamber and a 700 volt DC electric current at up to 20 kW is applied to the target. This produces a plasma from the target, and the plasma vapour is deposited onto the disc; it is an anode-cathode transfer. The metal coats the data side of the disc (upper surface), covering the pit and lands. This metal layer is the reflective surface which can be seen on the reverse (non-label side) of a CD. This thin layer of metal is subject to corrosion from various contaminants and so is protected by a thin layer of lacquer.
CDs are printed in waterless offset.
After metallization, the discs pass on to a spin-coater, where UV curable lacquer is dispensed onto the newly metallized layer. By rapid spinning, the lacquer coats the entire disc with a very thin layer (approximately 5 to 10 μm[3]). After the lacquer is applied, the discs pass under a high-intensity UV lamp which cures the lacquer rapidly. The lacquer also provides a surface for a label, generally screen printed or offset printed. The printing ink(s) must be chemically compatible with the lacquer used. Markers used by consumers to write on blank surfaces can lead to breaks in the protective lacquer layer, which may lead to corrosion of the reflective layer, and failure of the CD.
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As with records, the quality of the stamper is paramount. Much more so than with an analog record due to the magnitude of size. Get a CD from a first run and it wil KILL. Get one at the end of life of the stamper and it will, by definition, suck. There are only ones and zeros (on/off) in the ADC and DAC brains. The rest of the equation is prone to the weaknesses of all things analog.
What do you guys think?