The only write-up I could find online said
"Symphony is a new super high alpha acids variety released from a private company's breeding program in 1996. Its the first triploid high alpha acids variety in the US. Alpha acids content is almost 15% and beta acids content averages at about 4.7%. Total oil content is also high and storage stability is excellent, harvest maturity is medium-late with excellent cone yields averaging 3.000 Kilos per hectare.
Crop was decimated by the 1997 powdery mildew outbreak, and growers have agreed not to grown this variety again because it seemed to enhance the spread of the disease throughout the valley."
Makes me wonder where he got them if growers are staying away from it..
Also, there is some information on the DNA sequence of hops and symphony here