Shenzhen Marquess Electronics Co., LTD., founded in July 2004, is a joint venture of electret, microphone and ECM production established in China by AOI Motor Manufacturing Co., LTD.Company's production equipment and technology are introduced from Japan, with standard anechoic chamber, Denmark B&K audio analyzer, such as equipment, production to achieve the purification and dust-free operation, many sets of automated production equipment and strict qc architecture co., LTD makes us, the product has unique technology to guarantee the reliability and consistency of!I have been dedicated to the production, research, sales and service of canceling Direct microphone in 21 years, and have unique AOI professional understanding of proactive noise reduction and passive noise reduction.Our products are mainly exported to Japan, Europe, America, Korea, Hong Kong and other countries (regions).The current products mainly cover electret condenser microphone, microphone core, SMT microphone patch MIC, Dynamic microphone, MEMS silicon microphone, as well as the production, processing, research, development and sales of loudspeaker and PCB Assamble components.In 2002, the company passed the accreditation of Swiss general Notary Firm (SGS), and obtained the ISO9001:2000 quality system certification.April 2006: obtained ISO140001 environmental management system certification, all products comply with RoHs standardSeptember 2007: Obtained Canon Green CertificationJanuary 2015: OBTAINED UL certificationJune 2017: Obtained OHSAS18001 CertificationAOSPOW, 20 years experience in electret microphone production