Can A bad Tube sound bright and not musical.

The "wrong" tube can make the sound bright and not musical. Have you tried different tubes?

New tubes can tend to sound bright and normally do mellow a bit with some break-in time...

Probably just the wrong tube for your taste....

A malfunctioning tube can cause all kinds of problems including sounding bright, loud popping and distortion. Try removing the top cover and lightly tapping the tubes while the system is on. Listen for any unusual sounds. If a tube has become hyper-microphonic you will definitely hear it. If you have spare tubes you can try different tubes. If you don't have spare tubes get some, it's part of owning tube gear.

Rrog is correct IMO. Use a pencil's eraser end, and try swapping the position of the tube if it uses multiples of the same type-ie: a gain stage will be more sensitive than a follower stage. Therefore an unacceptable tube in one spot may work (mostly) fine in another. If it is a 6922/6dj8 I would surely try this as they tend to be microphonic.