Is there such a speaker...(loud but smooth)?

Depends on your price range..
Zu are very efficient needing very little amp power, concert level acoustics, very smooth, never fall apart, and can take abuse for hours on end due to using Pro based custom drivers... Also now using only Mundorf Silver oil caps on the highs so you will never get any grain at any volume, and they are all very compact at under a square foot floor space.
Good luck