Old American Baldwin Piano – Improve Pitch and Tone Adjustment 美国老款鲍德温钢琴-提升音高和音色调整 – New York Piano Tuner : I used ear tuning (also known as auditory tuning) and state-of-the-art software-based electronic tuning equipment for sound tuning. (The frequency for home concert tuning is 440 Hz.) 我采用耳调音法（也称听调音法）和最先进的基于软件的电子调音设备进行调音。（家用音乐会调音的频率为 440 Hz） Chen YN 调音主页