- Mar 9, 2016
- Riverview FL
The exact readout rate from the disc is unimportant since every CD player/transport necessarily buffers the data and sends to the DAC/output under the control of a crystal oscillator. The rotation of the disc is controlled such that the average data rate into the decoding stage is within the bounds set by the buffer.
I opened my disc player 25 years ago.
The CD spun at obviously incremental speeds, Slower near the edge, faster near the center.
I put my thumb on the disc to slow and even stop it, and it became obvious the output was not directly related to the speed of the spin.
There was no change in the output (audible) until the READ buffer ran out of bits to send to the obviously separately clocked OUT buffer, which, as I remember, took a couple of seconds on complete disc stoppage on that device. Momentary thumb slowing had no audible effect.