Spiro. I've got an EP Mittel G on there now, and as much as it adds to the set, it's just missing something.
Maybe try a Dominant. That what a few people use as spiro alternatives. Some people use the Dominant G because its the closest thing to a spirocore in the synthetic world (from what i've gathered). I liked it and honestly it felt natural with the set but I didn't like it enough to get a full set of dominants....i think. I'll go back in my records and see.
It's brighter. The Flat-Chromesteel G is even more bright. The Jazzer is another bright G string from Pirastro that could pair well with Spirocores.
I'm using the G and D because they feel like Spirocores but have more meat to the note. I always thought the Spirocore G and D sounded nasal and buzzy. Compared to Spirocore: Oliv G: Larger diameter, tuning issues, bigger tone Evah (Weich or Medium): more elastic and lacking the immediate note. I have the EP Weich atop Spirocore reds on my Kay and they are nice enough. I think a Superflexible G is a good option. The Zyex G is good too. It really depends on the particular bass.
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