The two problems I see are (1) scattered laser light getting into the photodetector and (2) the CDs tend to be out of round and thin and flimsy, so when spinning at high speed, they flutter, vibrate and wobble. If the transport was vertical the problem with vibration/flutter wouldn’t be so bad since gravity exacerbates the problem when the disc is horizontal. Unfortunately the Reed Solomon error detection/correction codes do not (rpt not) correct all errors AND the laser tracking servo mechanism cannot keep up with all the motion of the disc. The laser and the data are both nanoscale so it doesn’t take much relative motion to throw things off. Therefore, being able to control scattered light and CD vibration should be a high priority, since there is no way to recover losses of sound quality from either one. I.e., by the time the data gets to the DAC it’s too late!
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I asked how could a vibrating CD hurt the sound.
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That actually didn’t answer my question but that’s OK.
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Question, why you think CD vibration would hurt the sound? I mean, after all the player has error correction and a laser Servo Tracking system, no?
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Of course. All CDPs have a transport. The stray laser light fills up the transport compartment like a Christmas tree light. 💡
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Unfortunately the scattered light inside the transport reduces soundstage performance of all CDs. Palpability, stability, localization of musicians, separation of instruments and notes and the dimensions of the expanding, enveloping sphere. The fluttery, wobbly and vibratory nature of the spinning disc doesn’t help at all, making the sound slower, more diffuse and more compressed.
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You should be a reviewer. 😬
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Actually my point was, for a component with a foot on all four corners, if you remove one foot the component could easily topple over. You can get away with three cones only if you can arrange them in an equilateral or isosceles triangle. Three points may define a plane but four points are usually more stable.
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millercarbon, God gave animals and pianos four legs for a reason. He gave CD players four legs for the same reason. It’s so they won’t run around in circles. |
Quarter, dime, small ceramic tile, playing card, credit card, CD, industrial diamond, steel washer, aluminum washer. How will you know the CD is level whilst playing?
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I agree, ceramics kill brass. Brass is one of your softer metals. NASA grade ceramics are almost as hard as diamonds. Brass is waaay on down the scale.
geoffkait: this may be a dumb question, but unless components have some sort of threaded, adjustable feet, how does one "level" components?
>>>>Absolute level of the CD itself is not as easy to obtain as it seems. The tray level is not a good reference, sometimes the tray is at some angle to the transport. The level of the top of the chassis is not a good reference, either, because tolerances of the whole package are not exactly NASA precision. If you use a bubble level on the top of the chassis what you often find is the level varies. So, which one is correct? If the component does not have threaded feet you will have to come up with a shim or two under one or two feet.
Also, “fuzziness” is not unusual for ANY CD player. Everything is relative for resolution and dynamics. Unless one addresses scattered background laser light AND flutter and vibration of the CD whilst spinning I’m afraid you’ll always be on the fuzzy side of things. It’s always gaining to be fuzzy and compressed relative to what it should be. People give designers of this stuff way too much credit. |
If one transport is level and the other one isn’t guess which one will sound better. And have a better and more revealing soundstage. The first two guesses don’t count.
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