Music therapy is often used where more conventional therapies are not as likely to be as accepted or tolerated.

本句，Music therapy is often used 是主句，where 引导地点状语从句。

这两个as，纯属多余，因为没有可比较的对应项。直接去掉即可：

Music therapy is often used where more conventional therapies are not likely to be accepted or tolerated.

【翻译】音乐疗法经常被用于传统治疗不太可能被接受或容忍的地方。

be likely to do sth. 可能做

be likely to be done. 可能被做