GB/T 33723-2017乐器声学品质主观评价人员等级规范国家标准
英文:Grade requirements of subjective evaluator for the acoustic quality of musical instrument GB/T 33723-2017介绍: 国家标准《乐器声...
英文:Grade requirements of subjective evaluator for the acoustic quality of musical instrument GB/T 33723-2017介绍: 国家标准《乐器声...