"Theoretical reasons" vs "theory reasons" for describing reasons which come from the theory of something

Imagine you are studying music. The theory of music tells you that note 1 sounds good next to note 2. You want to reference this in something you are writing. As I see it, there are two ways. The first is to write, "for theoretical reasons, note 1 sounds good next to note 2." The alternative is to write "for theory reasons, note 1 sounds good next to note 2." The issue I have with the former way to write it is that it could be interpreted to mean the reasons themselves are theoretical. How to get rid of the ambiguity?

Edit: since the analogy seemed to be clouding things I will write more or less explicitly what I have in mind. I am writing a paper in mathematics. I have the following sentence I wish to communicate:

"The object is of interest, not only for reasons arising from the theory, but also for reasons arising from practical applications."

Of course I could just write the above, I know that, but I am curious about alternatives or the particular use of "theory reasons" which i think shouldn’t unaccepted (although I have been sufficiently convinced it’s unacceptable here).