And the slight variations in frequency that do exist are only a tenth of the difference between a C and a C sharp.

即使有差异，也是极其微小的，只有C调与升C调之间音高差异的十分之一。 《美国声学学报》电子版刊登了上述发现。

youdao

Be careful C it is very sharp, with teeth just like a saw.

VOA: special.2009.06.30

We can't go C, D, D-sharp, F.

不能是C,D,升D,F

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