How to notate an interval going below the root…

[danonearth]

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Hi, I was posting in another thread, and a unique question came up about how to notate an interval going below the root…[/size][/font][/color]
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So, for example in ‘Stand by Me’, the progression is: I-vi-IV-V[/size][/font][/color]
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However, personally, I would notate the ‘vi’ dropping below the root with a ' - ' (minus symbol), but that is just for my myself... I was wondering if there was an accepted or professional standard that I should adopt instead, which might be more widely used and understood? [/size][/font][/color]
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Thanks![/size][/font][/color]

[NoirBass]

You wouldn't normally show whether it was above or below the tonic chord as its largely irrelevant.
I think you are slightly misunderstanding the role of the Roman numerals. They are to show the chord progression in any key, it doesn't matter if you voice the VI chord higher or lower than the tonic chord.
When you talk about intervals you are talking about single notes, not chords.
If you do want to stipulate intervals in a baseline or melody(single notes), you should notate the part written in dots. That way there can be no error in conveying the right line.

Edited April 11, 2017 by NoirBass