Dr. Muzammil H. Siddiqi, current President of the Fiqh Council of North America, states: “The general rule about Jama’ah prayer is that the lines should be connected and those who stand behind either see the Imam or those who are praying behind the Imam. If these conditions are fulfilled then you can pray in your hotel or on the streets. Following the Imam simply by hearing the voice and not seeing the Imam or those who are praying behind the Imam would not fulfil the requirements of congregational prayer.”
Allah Almighty knows best.