This paper presents a method to extract rendering matrix on multi-channel audio signals as an object fed to Moving Picture Expert Group Spatial Audio Object Coding (MPEG SAOC) encoder. This technique allows MPEG SAOC to transmit multiple multi-channel audio objects, instead of only a single multi-channel background object as specified in MPEG SAOC standard. Listening tests show that the proposed method does not only provide a new feature to MPEG SAOC but also achieves higher audio quality than MPEG High Efficiency Advanced Audio Coding (HE-AAC), the conventional standard for delivering object-based audio content.