bi-harmonic

例句：

1. 1. The music is bi-harmonic and very soothing.
   这首音乐是双谐调的，非常舒缓。
2. 2. The melody has a perfect balance of pitches, making it bi-harmonic.
   旋律的音高完美平衡，使其成为双谐调的。
3. 3. In the orchestra, each instrument plays in harmony with its neighbors, achieving a bi-harmonic effect.
   在管弦乐队中，每个乐器都与其邻居和谐地演奏，达到双谐调的效果。