Question about fingering

Maybe this is a dumb question, but I’m wondering this since a few days ago..

In a whistle in the key of D, if you play OXXOOO you’ll be playing a C-natural, but if you do that fingering (OXXOOO), for example, in a whistle in the key of C or F or whatever, which note I’ll be playing?

Thanks in advance,
Martin

You’ll always be playing the note one whole step down from the tonic note of the whistle.

On a D whistle, it’s C-natural.

On an E whistle, it’s D.

On a G whistle, it’s F-natural.

On a C whistle, it’s B-flat.

Make sense?

–James

On a C whistle you would be playing B Flat and on an F whistle E Flat

Of course, that makes sense. Thank you very much!!

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