Without model number we can't know what connections you have available.
If the Sony only has composite video+audio outputs and the Samsung doesn't have the corresponding input (check the manual) then you would need an active composite video + audio to HDMI converter.
If you got the reverse converter it won't work.
If you got a composite video to HDMI converter without an audio input then you would not get sound.
If you didn't connect the audio output of the Sony to the converter then you would get no sound.
If you want sound from the TV to play through the Sony you will also need to connect the TV audio output to the Sony input. A different converter might be required to do that.