I think the differences are more about build quality, features, and the ability to read cds ie error correction, buffer etc. I’d like to think my McIntosh transport sounds better than others, and maybe it does, but it can read cds other players can’t and it also has the ability to accept and play dsd files from a USB thumb drive. My two cents.
If the DAC is the same, how different do CD transports sound?
One interesting topic of discussion here is how audible the differences are between CD players when they are used as transports only — or when they are only transports to begin with.
In other words, in a comparison which keeps the DAC the same, how much difference can be heard between CD transports?
This recent video by Harley Lovegrove of Pearl Acoustics provides one test of this question. It may not be the ultimate test, but he does describe the experimental conditions and informations about the qualifications of the listeners.
He comes to the main conclusion here: https://youtu.be/TAOLGsS27R0?t=1079
The whole video is worth watching, I think.