Matrix Development

A group of authors at the IRT in Munich, Germany, have studied the performance of newer matrix encode and decode methods compared to conventional matrix Dolby Surround encoding and ProLogic decoding. In a AES (Audio Engineering Society) Preprint 4736 entitled ìAssessment Of 4-2-4 And 5-2-5 Surround Sound Matrix Systems,î Circle Surround and Lexicon Logic 7 Surround (but curiously not Fosgateís Six-Axis Surround) are compared. ìThe results, with respect to the overall quality of the tested matrix systems (encoded and decoded), show that the performance of the tested matrix systems strongly depends on the test item.î On applause, Gospel music, and ice hockey, there was no significant difference. On the six of nine test items in which a difference was significant, the 5-2-5 matrix of Lexicon was preferred in 75 percent of the cases. All of the systems suffer compared to a 5.1 channel discrete original.While there is no doubt that any matrix system would ìsufferî compared to a 5.1 channel discrete original in particular aspects, the source of this report, a professional journal, Surround Professional, did not specify the test conditions nor how Lexiconís matrix was encoded or if, in fact, it was encoded, because to our knowledge Lexicon has no encoder but is a matrix decoding process as is the Fosgate Six-Axis matrix decoding process. Circle Surround does have both and encode and decode process as does Dolby Surround. Once the AES Preprint becomes available we will analyze the testing and results more carefully.