Interesting analog experience

I while back a bunch of my die hard analog loving buddies and club members came over for a night of music etc .
It happened that I was listening to a CD when they came up the walk way , so I put a record on but left the preamp on the CD input . After about 20 minutes of listening to these good folks tell me how great the sound was and how great analog was the record came to an end but the music continued. I broke it to them that they were enjoying digital sound . I know it was kind of sneaky but seeing there mouths agape and them being speechless was worth the price of my S.M.E. 20/12 table .