Choral Support (Teamwork Feat) and Concussive Spell Metamagic

[Red Griffyn]

I've wanted to build a sonic evoker for a while now, but it has always been nigh impossible to swap elemental types to sonic. With the release of the new Distant Realms Campaign Setting there is a teamwork feat available that allows an ally to change your elemental damage dealing spells to sonic sonic damage with a DC 10 perform (sing) check. The obvious build for this is a valet archetyped familiar who tries to sing with you and aid you're casting by changing damage subtypes. Here is the link to the feat description:

https://www.aonprd.com/FeatDisplay.aspx?ItemName=Choral%20Support

My question is whether I can add Concussive Spell as metamagic (i.e., prepare a concussive fireball with it, or use an arcane bloodline sorcerer to spontaneously add it) because it says the damage is sonic. It doesn't explicitly say the spell descriptor changes to [sonic] so I was unsure if this would work RAW or whether changing the damage in that way is synonymous with changing the descriptor.

[blahpers]

Choral Support doesn't change or add to the descriptor of the spell; it only changes the type of the damage dealt, and then only if the Perform (sing) check succeeds. A fireball remains a [fire] spell and does not become a [sonic] spell. Thus, it wouldn't work with Choral Support, but would continue to work with things like the pyromaniac gnome racial trait or the solar bloodline arcana despite doing sonic damage.