I am playing on a bass with what appears to be a mixed set of Pirastro strings. The set sounds, and feels very nice, except for an E that is a little dificult to get vibrating. I would like to get the same setup on my own bass, but I can't identify one of the strings. Based on my research on Pirastro web site, the D and G strings appear to be Flexocor (solid Ruby ball end, and Red/D and Brown/G peg end). The E and A strings appear to be Flat Chromsteel (White with Ruby spiral on the ball end and Green/E and Yellow/A on the peg end). There is the mystery, Pirastro lists the FLat Chromesteel A as having a Black peg end. They do list an "H5" string with the Yellow peg end. The "A" string on my bass certainly looks seems like a normal A, in thikness, tension and tone. Can anyone explain please?