Before you move your rack, listen to your kit with the single RCA cable that you presently have in place, establish a sonic reference. Than try adding the additional RCA and adapter... and listen again. Repeat if necessary. Then do what you have to do.
In theory, everything counts, every interconnection becomes a bit of a degrade. In the extreme, in practice, audiophiles have been known to hard solder patch lines from one component to another with huge gains in overall transparency (that's right, no IC's), though impractical for most of us, it is a cleaner, simpler path.
Let your ears be the final judge.
Happy Listening!
In theory, everything counts, every interconnection becomes a bit of a degrade. In the extreme, in practice, audiophiles have been known to hard solder patch lines from one component to another with huge gains in overall transparency (that's right, no IC's), though impractical for most of us, it is a cleaner, simpler path.
Let your ears be the final judge.
Happy Listening!