every enclosure is tune at some point.
untuned doesnt means tht it has no tuning at all. its just tht u dont know or u not sure about the tuning point.
first decide wat type of music u hear. 30-35hz if u want to catch all tunes. wont be to loud to the ears but its going to sound nice.
35-40hz its going to be alot of output. ur ears will for sure catch the loud output. but has a flaw.... many english songs or bass tones will not sound good .