How to substract one speech signal from another to check the difference between them in Simulink?

Hello everyone,

I am working with delayed speech signals. I would like to know the difference between one speech signal and another one which has been delayed. I have tried to use the add block (using minus) but it does not seem to give the right response. I am working in Simulink.

Many Thanks

[Philip Caplan]

Can you provide more information as to why the response is not correct? The "subtract" block should give the desired result. Can you also attach the Simulink model?