According to Official Guinness Records,
The largest shofar ensemble involved 1,022 participants at an event organized by The Partnership for Jewish Learning and Life in Whippany, New Jersey, United States on 21 September 2014.All participants created the following sounds on their own Shofar the T’Kiyah, Sh’varim and the Tru’ah.
For a complete list of 2014 records, please visit 2014 Guinness Records in United States.