Located in the Great Bazaar, Tatya's Cacaphony is a music shop selling musical instruments and sheet music alike.
Tatya's Shop Edit
The musical instruments which used to be for sale in the Festhall have been moved to Tatya's Cacaphony. This includes both normal musical instruments, and magical instruments. The Festhall still sells normal musical instruments.
All instruments (magical and normal) have been updated to work with the TKL performer tool. Instruments purchased previous to the addition of this area may not work with the performer tool. Available instruments are the lute, flute, drum, and lyre (using the lute sounds). You can buy bagpipes, but there is no "bagpipe" version of the performer tool.
Tatya also sells a few pieces of sheet music. These can be used (and modified) to get you started with the TKL performer.
Musical Lights Edit
The will o' wisp NPC on the second level of the shop can improvise music, play known songs, and sell sheet music of its improvisations. Improvisation is basically randomized music with certain instruments and chords; sometimes it will sound good, sometimes not so much.
Playing a song is 10gp. Getting a copy of sheet music is 25gp.
TKL Performer Edit
The performer is a tool for bards that allows them to play single notes or whole customized songs. A tutorial on how to use the performer can be found here.