Custom key signature (Turkish Arel-Ezgi-Uzdilek system) on transposing instruments

Dorico
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Hello! Please find attached my score. Starting at bar 105, I’ve created and assigned a custom Key signature for the two clarinets and nobody else. It all looks good in the score, but the clarinet parts stop to transpose when it gets to this part! The part becomes ‘in C’ for those few bars of the microtonal Turkish key signature. I have included all the accidentals needed (even the ones I am not using in the score) so that Dorico can calculate how to transpose it in the Bb part. By the way, the key signature I’ve created looks open just like C major, because I want the microtonal accidentals to appear only when they are needed. This is a short passage. I will have the clarinets go back to the Western well tempered system only after a few bars. Perhaps this has to do with the definition of the clarinet itself? In the setup mode, the Bb clarinet is defined as transposing -2 half steps. But in this particular passage it should transpose 4 EDUs. How do I tell it to transpose differently for a temporary passage? Or, how do I tell Dorico that in the Arel system I’ve created, 4EDUs=2 EDU’s until the next standard key signature appears? Please help :folded_hands:

2. Bölüm Yürük Semai.dorico (3.3 MB)

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I suspect the problem here is that transposing instruments in Dorico all transpose by 12-EDO intervals, so a Clarinet in Bb transposes by 2/12ths (or 1/6th) of an octave. 1/6th of an octave isn’t a valid interval in 25-EDO, which is why this doesn’t work. I think you’ll need to come up with a tonality system that allows for division by 6ths and division by 25ths, e.g. 150-EDO.

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Thank you for your reply, Richard. I did it: I edited the Arel tonality system so it now has 150 EDU. One isse with this is that 150 divided by 12 makes 12.5, which is not an option in Dorico’s Edit Tonality System dialog. So I got around it by defining most of the whole steps to have 25EDUs, half steps to have 13. I set G-A to have 24EDU’s so that I get 150 division per octave. Then I adjusted my microtonal glyphs accordingly. The result is the same. The clarinets are still in C for the duration of that passage. Please have a look:

2. Bölüm Yürük Semai 150EDU Arel.dorico (3.3 MB)

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I tried again with 300EDUs which is dividable by 2, 12, 5 and 6, making everything symmetric. It worked this time! Thank you! Problem solved!

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