When I’m trying to create new stuff, it has to be no-voice. Multiple genres are ok, but words are distracting. Quiet always works, too. For wtf debugging, anything with a hard edge is good. (Voice or not). I’m either idling awaiting inspiration or chasing an idea. If the latter is deep enough, the music sorta goes away.

I believe every study has shown music of any kind results in a 0x to 0.5x productivity hit.

There is nothing to settle - it is all about personal preference. You would also need to define what "best results" even means. Measuring dev productivity is a notoriously bad idea, so I just go with "That which makes me enjoy the work the most."

That being said, I waffle between 90s singer/songwriter music, 80s alternative rock, and a constant soundtrack of Joan Armatrading.

electronic

Depending on my mood, anything from death metal to elevator-music jazz. I usually settle on some kind of house/trance with a pulsing beat, though. That's mostly when I know roughly what I'm writing, and I'm just getting the code in place.

And then, after working like that for a couple hours, my brain flips and I need as close to perfect silence as I can get, so I pause the music.

Check out: musicforprogramming.net

For me it's instrumental. Language distracts me. I also do well with something that has a groove. Some type of funk seems to work really well. YouTube has all kinds of instrumental funk music that works well.