45ed4

The 45 equal divisions of the fourth harmonic is a tuning system equvalent to 22.5edo, representing every second step of 45edo.

Its step size is very close to the Alpharabian quarter tone 33/32. In addition, it tempers out the tritrizo comma in the 4.7/6 subgroup, and along with it the quartisma in the 33/32.7/6 subgroup.