ET?

We need to listen and control the tone when playing alone as well as when playing with others. In particular, on a C instrument, the D is unreliable. On an F instrument, the G is. No doubt the corresponding note on the various whistles is the same.

In a workshop I learned to add a finger, starting at the bottom, until the high D was in tune. (That's for when the D is long enough to bother about.)

At my church we have piano, violin and recorder. Our violinist says that during heating season, the piano gets sharper throughout the service. I deal with this by listening to the violin like crazy. All I ask myself is, "Are our notes the same?" Apparently it works.

Thanks for your observations, Tootler. I just bought a Yamaha plastic soprano as a gift for a friend. It played a nice scale from low C up to high G. I rejected the first one I tried because its highest notes were too furry. They were in tune, though.