Audio Systems: Recording, analogue to digital, golden ear

Question
How can I tell the difference between a track recorded analogue and a track recorded digital, from the finished product?

Answer
Well, it depends on what the finished product is!  If it is an MP3, then by definition it is a digital product.  But, I think you want to know about the original track recording.  Any original recording, made on either a digital or analogue recorder, can easily be converted; analogue to digital or digital to analog.  Therefore, depending on what process is used, there may be conversions that you don't know about.

In a commercial product like a CD, which is clearly a finished product that is digital there is no way to know for certain if the original track and the mixdown was in digital or not. In fact, some popular music may have both; if it is a 16 track original some of the tracks may have been analog and some digital.  Assuming that it is an all digital master recording, then mixed down to 2-track digital (or 5.1, etc.) and put on the CD (or dvd) you can sometimes tell by listening to the quiet sections and detect the noise sound.  An analogue recording will have some low level "hiss" sounds that are not present with digital recordings.  But, that is not a guarantee.

Some "Golden Ear" listeners, very experienced in what to listen, for claim the can hear the difference in the recording claiming that digital recordings have sounds caused by the sampling that makes is possible to detect the difference.  I don't believe this to be true as I have personally given blind listen tests to various recipients and they don't pass the test very well!

Hope this helps.