Measurements and conclusion
Contents
We measured the ATC CD2 on our Aeroflex PN9000 phase noise analyzer. We are using the Aeroflex SGD-3 as a reference. The SGD-3 uses the 10 MHz reference of the PN9000. We use an active probe to send the clock signal to the Aeroflex.
We measure two frequencies: 16.93 MHz and 2.822 MHz. The master clock is 16.93 MHz. This frequency is divisible by 2.822 MHz (comes out six). This 2.822 MHz clock is used when converting 44.1 KHz material. After all, 44100 times 64 is 2.822 MHz.
Phase noise measurements ATC CD2
We have to say: these are fine scores for a CD player in this class. Only 2.22ps jitter on the main clock and 3.29ps on the 2.822 MHz clock are just neat values. We are not measuring on the clock itself, that could result in even better values.
Allan Variance is also neat with 253fs on the main clock and 1.97ps on the 2.822 MHz clock. In short: stability of the clock is also very good.
These neat values will also help when driving an external dac, should you ever want to upgrade to a nicer converter and use this CD2 as a drive.
