奏効 is read as そうこう (soukou) and means efficacy.
そうこう
soukou
かなでる
to dance
そうしゃ
instrumentalist
success
そうほう
way of playing (an instrument)
そうがく
musical performance
そうする
to accomplish
そうほうきごう
articulation mark
そうじょう
report to the Emperor
かなであう
to match
そうもん
reporting to the Emperor
そうせい
petitioning the Emperor
そうきょく
sonata