Alves.hs

-- | Bill Alves.
module Music.Theory.Tuning.Db.Alves where

import Music.Theory.Tuning.Type {- hmt -}

{- | Ratios for 'harrison_ditone' (SCALA=pyth_12)

> import Music.Theory.Tuning {- hmt -}
> let c = [0,114,204,294,408,498,612,702,816,906,996,1110]
> map (round . ratio_to_cents) harrison_ditone_r == c

> import Music.Theory.Tuning.Scala {- hmt -}
> scl_find_ji (harrison_ditone_r ++ [2])
-}
harrison_ditone_r :: [Rational]
harrison_ditone_r =
    [1,2187/2048 {- 256/243 -}
    ,9/8,32/27
    ,81/64
    ,4/3,729/512
    ,3/2,6561/4096 {- 128/81 -}
    ,27/16,16/9
    ,243/128]

-- | Ditone/pythagorean tuning, <http://www.billalves.com/porgitaro/ditonesettuning.html>
--
-- > tn_divisions harrison_ditone == 12
-- > tn_cents_i harrison_ditone == [0,114,204,294,408,498,612,702,816,906,996,1110]
harrison_ditone :: Tuning
harrison_ditone = Tuning (Left harrison_ditone_r) Nothing