# Irrational time signatures

I’m currently working on a piece where I start in 5/4, then start playing in a 4/4 feel over it ( a 4:5 tuplet). Then I play a time signature that is 1|16th shorter than the 4/4 feel over 5/4. This would amount to a 15:399-tuplet over a 399/320 time signature, if my math is correct.

Which I think it is, as:

• 1/64th of 4 equals 1/80th of 5

-(5-(1/80*5))*80=399

• 4*80=320

So, the time sig would be 399/320

-16-1=15 as far as the tuplet is concerned

This is probably possible in Dorico, but Cubase does not seem to let me to do it in a time signature track. As I usually add audio tracks and finalize production in Cubase, this would be cool.

Of course, I could calculate a pretty accurate tempo change and write it in 15/16, the latter so quantizing would be an option. But I would prefer this for the perverted reason that I do not see a reason to write a tempo change. Writing an irrational time signature would be closer to the way I feel the music.

Another question is regarding compatiblity of Dorico and Cubase in these matters. Would it work if I imported a MIDI-file of such a score into Cubase from Dorico? Would I be better off if I just wrote a metric modulation if I want to finalize production in Cubase?

You’re right: 4/4 − 1/16 = 15/16. The latter is what you should enter on the signature track on the bar where you want the change to take place. Note, it’s a signature change, not a tempo change.

This would also require a tempo change, as the pulse starts out in 5/4, then changes to a 4/4 feel over 5/4. The 15/16 would be derived from the 4:5 tuplet. This is very possible in Cubase, but an irrational time signature would be infinitely cooler.

Well, that means you have two changes happening in your performance: one in signature, another one in tempo. Use those respective parameters in Cubase to control them.

I know this is very possible. OTOH, it’s a bit sad that Dorico seems to support irrational time signatures, but Cubase not so much.

My original post was basically a feature request and a question about compatibility of Dorico to Cubase. Both regarding irrational time signatures.