Yes a little and also the cabinet will get more excited with the speaker more inside than outside and that will create some coloration to the sound- if you can get it out- even a few cm- it would probably help a little bit. Unless its designed to be an in wall speaker, putting anything in a cabinet is not helpful to the sound. I realize this is done for aesthetics and thats a real consideration, if something is unpleasant to look at, you won't enjoy it as much.

Best regards,
Jerry
Main System: 861v6, DSP8000s in corners, DSP7000s Center and Sides, 1-9 humans.