Recommend me a bright musical Bookshelf speaker.

Triangle Comete

I'd venture to say Selah Audio Tanzanites would fit with your requests.

Thank you for great info and suggestions.

When piano sounds like a piano and strings sound like actual strings and not like a fishing line strung over a plastic bucket.

I know exactly what you mean in your description....this hyped sound is what most people actually want and it is hardly surprising that manufacturers make what sells!

Try ATC SCM 19 or 20. These are particularly natural sounding and very convincing on piano. Telarc use the 20's for mastering so these are on the neutral side of neutral.

Silverline Audio SR-11s have a natural sound. Although I wouldn't consider them bright, they definitely aren't "boomy." For me they work best on stands at least 26 inches high.

KEF monitors may work.

You might want to try Triangle or Focal.

Reference 3a DaCapo or Zu Tone. Both are crossoverless and full-throated.

Coincident, Reference 3A DeCapo.