A friend of mine bought a HSS strat. I'm just wondering how that humbucker affects tone? Do you play different stuff on a strat with HSS configuration than one with SSS?

A HSS Strat is an incredibly versatile instrument. The humbucker allows you to play 'heavier' stuff like Zeppelin, Sabbath, while retaining the ability to play SRV and Hendrix material at the mere flick of a switch!
I play in a copy band and an HSS is an indespensible tool !

As far as TONE.
You will lose the single coil Strat sound (unless you do the split coil wiring thing) and position 2 might not be as "Sweet Home Alabama" as one might like; but you will gain the humbucker CHUNK!

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