Anyway, back to the subject of tuning by perfect ratios.
I’m just using this VST instrument example to demonstrate. Yes, as you observed, Cubase can only tune VSTs that specifically implement that function: that includes some Steinberg multitimbral synths, Some VSL libraries and a few others.
You really can’t hear it?
Just Intonation (Hermode Active)
Equal temperament (Hermode not active)
A Cubase project
Hermode.zip (664.5 KB)
Anywho, As far as “tuning by ratios” goes, There has to be a note used as reference. Then the note to be tuned is calculated from that. The Hermode feature does this on the fly, it dynamically calculates the tuning, and which note to use as the reference during playback.
So, are you hoping to select a note and then apply the ratio, getting the result of a second pitch?