Just put flatwounds on my '74 Jazz. First time I've ever used them. I have Ernie Ball 45-100 nickels on all my other basses, so went with Ernie Ball 45-100 steel flatwounds and am in heaven. The '74 jazz with flatwounds (after a few days of playing to take away that new string brightness) sounds amazing through all amps I've tried, as well as with headphone practice amp. I'm using absolutely no effects, processors, preamps or eq and I'm addicted. All my favourite players use roundwounds (Marcus, Wooten, Bona, AJ, Will Lee), but everytime I pick it up I can't get over it.