According to Official Guinness Records,
The largest microphone is the ‘Qoros Super MIC’, measuring 5 m (16 ft 5 in) tall, 3.1 m (10 ft 2 in) wide and 2.3 m (7 ft 6 in) deep, created by Qoros Automotive Co., Ltd and was measured in Shanghai, China on 6 November 2014.
For a complete list of 2014 records, please visit 2014 Guinness Records in China.