How to completely turn off voice control on my Galaxy S7 Edge?

You can use either S Voice or Google app (OK Google) to use your voice to do things on your Galaxy phone.

If you don’t need the voice command feature, you can disable S Voice and stop Google App from responding to your voice.

i. To disable S Voice
1. From the device’s Settings, tap Applications > Application manager
2. Find and tap S Voice App.
3.Tap Disable.

ii. To stop Google App from responding to your voice

1.Open the Google app. (By default, it’s in the Google folder)
2. Tap the Menu button > Settings > Voice > “Ok Google” detection
3. You can turn off all the voice detection options here.