See Marvel family #Marvel for technical data.
One way to do this is to take the conventional circle-of-fifths notation with an additional module of accidentals for the 81/80 comma. In this system, 5/4 is a major third, 7/4 an augmented sixth, and 11/8 a double diminished 5th.
|5/4||Down major 3rd||C-vE|
|7/4||Double down augmented 6th||C-vvA#|
|11/8||Triple up double diminished 5th||C-^3Gbb|
Alternatively, it can be notated the same as full prime-limit just intonation, with a distinct accidental module for each prime harmonic. That makes some intervals more intuitive, at the cost of hiding the structure of marvel tempering. For example, it is customary of the 5/4 to be a major third, and 7/4 to be a minor seventh. As a result, the fact that the 14/9 is a stack of two 5/4's is not revealed, and the related chords can be confusing.
Marvel hobbit scales
Undecimal marvel hobbit scales
Other marvel scales
This spectrum assumes pure 2 and 7.
|15/13||700.916||383.497||15-odd-limit hecate minimax|
|13/10||701.065||383.348||13-odd-limit hecate minimax|