Is there a difference in sound quality when streaming TIDAL Vs CD player


I hard wired my modem located in my family room using Cad6 cable to my Apple TV and direct wired my Apple TV to my ARCAM AVR550.  I have an OPPO 203 connected by both an RCA cable and by HDMI to my ARCAM.  

The dealer I purchased my ARCAM from told me to play my CD’s through my RCA connection and to watch DVD’s through HDMI.  If I listen to CD’s through the RCA, aren’t I using the DAC on the OPPO player rather than the DAC on my ARCAM and wouldn’t the DAC on my ARCAM be a better DAC.  My friend told me I should use a digital cable rather than an RCA to improve sound quality to utilize the DAC on my ARCAM?  If this is the case, wouldn’t the HDMI be the same as by using a specific digital cable?  I listened to my CD’s through the RCA Vs the RCA cable and I thought it sounded better through my HDMI cable.

i will be looking forward to your responses.

Thank you,
128x128larry5729
I have a dedicated CD player and rarely use my Oppo for listening to music, and when I do it's mostly streaming of the music files on my network, but when I do I have it connected by coax (rca) to my Auralic Vega DAC which results in much better sound quality.
To Mahler123;

Is there an additional port on my OPPO where I can connect a digital cable or is my HDMI cable good enough to use as a digital cable.  Also, when I was getting started in this hobby, I wanted a system where I could listen to both 2 channel and home theater.  The dealer I purchased my ARCAM told me an ARCAM was a lot better than others.  I originally wanted to buy a Parasound integrated amp.  Would the Parasound amp have sounded better.  In retrospect I wish I had purchased 2 channel preamp and amplifier and concentrated on just 2 channel.  However, had I done so I was not sure how I would have been able to use the room for both 2 channel and for home theater.  Just wish I was rich and had a wife would allow me to spend more money on this hobby.  Looks like once you are bit you get hooked on this hobby.
You should listen for yourself. No difference = no worries.

The big advantage of HDMI in this case is the multi-channel and bass management in your receiver.

Best,
E
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Would the sound quality have been better had I purchased a Parasound integrated amp as opposed to the ARCAM AVR550 I purchased.