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Yes.
If the original speakers had ports, the drivers will probably struggle with a sealed enclosure - not surprisingly, there are several other factors as well.
Back in the last century, if any of my students wanted to design speakers I used to make them read a book first:
https://books.google.co.uk/books/about/An_Introduction_to_Loudspeakers_and_Encl.html?id=HmNfAAAACAAJ&source=kp_book_description&redir_esc=y
Doubtless this newfangled interweb thing has the equivalent of clear explanations with pictures...
Related question. Do I need to include a similar tube/opening at the top of the speakers that I'm replacing the case for?