Not just hip hop. Irving Berlin used a transposing piano eighty years ago.jeromejenkins wrote: ↑Mon Oct 31, 2022 4:22 am I have heard many successful and even platinum selling Hip Hop producers say they just learnt how to play one Major scale (C Major typically as its all the white keys) and one Minor scale (C Minor is good aswell or A Minor as it is also all the white keys) on the keys and then whenever they wanted to play in a different key they just just used a pitch/transposition plugin in there DAW to shift the scale up or down as many semitones as needed.
https://en.wikipedia.org/wiki/Transposing_piano