testing cd player output impedance


Does anyone know how to properly test the output impedance of a cd player ,I have a sony dvp-9000es dvd/cd player and need the info to make a passive preamp
jasljs
The manual does have some specs but I am not clear how to interpet the two specs,They are load impedance which it says (over 10 kilohms) and output level at (2 Vrms at 50 Kilohms).I thought it woud be best to test to get a acurate impedance value .Do you Know Which is right? 50 kilohms seems hight for a cd source impedance
The 50 k-ohm is the impedence of the cd input of the pre-amp or receiver. Most are 47 k-ohm with an input sensitivity of 150 mV.

Hope this helps.
Rich