^ d- labella is only low tension bass strings so far...

the pricing has less to do with design, than materials....it's the pure nickel wrap that drives the cost up..not the inner core steel wire..hex vs round

the string manufacturers use the term core to wrap ratio...that's the size of the inner steel core (round or hex) to the outer wrap ratio (flat or round)...obviously a thinner inner core on the same gauge string will give less tensiony feel...and further, with pure nickel being a softer material than stainless steel, will feel better on fingers as well


hex core's advantage is that it makes stringing the guitar easier as the wraps won't separate as easily if cut or improperly strung



cheers


ps- all strings, very early on, were round core, but john d'angelico in the 1920's or 30's wanted the 80/20 bronze strings he used with a different type core..so that the windings wouldn't spread...and talked to the d'addario family about making a different core..thus hex core was born...it was d'angelico in union with the early d'addario family...way before the company became known as d'addario!!!...that was fairly recent!!..i had fam working at d'addario...