Method and device for reducing telephone call costs

A gateway system comprising:

• a local-call device for receiving and sending phone call signals from and to a telephone device located in a same telecommunication zone;
• a VoIP device, distinct from the local-call device, for receiving and sending VoIP call signals from and to a remote and distinct VoIP device located in another distinct telecommunication zone;
• a voice transmission apparatus comprises a set of two acoustically distinct chambers comprising:
• a first chamber comprising a first microphone and a second speaker;
• and
• a second chamber comprising a second microphone and a first speaker;
• wherein the first microphone and the first speaker are in communication with the local-call device only and the second microphone and the second speaker are in communication with the VoIP device of the gateway system only.

A voice transmission apparatus comprising:

• a body defining a set of two acoustically distinct chambers comprising:
• a first chamber comprising a first microphone and a second speaker;
• and
• a second chamber comprising a second microphone and a first speaker;
• wherein the first microphone and the first speaker are in communication with a telephone device only and the second microphone and the second speaker are in communication with a VoIP device only.