I scheduled a tuning on a piano that's "not too old, but not new, either."  Customer says that a few tunings back (I'm hearing at least five years ago) a bass string broke... oops, she said "one of the lower strings on the left" broke... during tuning. Tuner replaced it, but "you know how new strings are... they keep stretching" and it doesn't hold a tune. Now, I'm thinking that perhaps it was replaced with a universal string and maybe it's the <tone>, not the <tune> that gets her attention. Do (universal ) bass strings continue to stretch considerably more than plain-wire treble strings?? Thanks, Paul Bruesch Stillwater, MN