Tā shì kēbān-chūshēn de gāngqínjiā, jīběngōng fēicháng zhāshi.
She is a formally trained pianist with very solid fundamentals.
Tips
culture
科班 originally meant the Peking Opera training troupes of the Qing era, where children received rigorous classical drama training. It generalized to mean 'formal training' in any profession.
usage
Commonly negated, 不是科班出身 ('not formally trained') is used to praise a self-taught person who nonetheless excels, or to dismiss a pretender.