the first wound gut string are mentioned by Brossard ( 1712 ) and Forqueray (1767) ( look at
www.damianstrings.com ). plain gut are only use by slappers ( blues, hillbilly, western swing, and balkan music, don't forget that slap bass is balkan technique with a very long tradition it's not born in usa !!!...) for a smooth slap sound, "all gut string player" use wound E /A and plain D /G , in 60's many bassist use a complete wound gut , OLIV, EUDOXA, and now PIZZICATO (
www.pirastro.com ), this is the only gut maker to make different wound, real fat silver, round silver, flat chromsteel, for me the best gut set is Pirastro CHORDA, if you want PC sound ( or blanton, pettiford, stewart... ) try this one you don't regret it...( sorry for my english)