I decided to post this in the parents forum because I believe there to be some parents who are very educated on this topic
I am considering attaching a vocal supplement to my application to Brown University - this is the only Ivy to which I am applying. I have high grades, 4.34 weighted GPA, 34 ACT, etc and I want to add this to my application because it’s a huge part of who I am. I am an accomplished musical theater actress who has performed with a variety of audition only young adult companies.
Is it helpful to attach the supplement? Or is it just distracting?
I would appreciate any and all advice. Thanks so much
If you have talent and it is about who you are, I say do it. There are not many places on the application to really be you outside the essays, so if schools allow it you should do it.
This seems to the case where you should attach a supplement.
If you’re really, really good (and have been recognized by experts as being really good), attach it. Don’t attach it just because it’s a big part of who you are.
You are clearly very talented, and your talent has been recognized. You should definitely do a supplement. For one thing, you’ve spent a great deal of time getting to this level. I think it’s not so much a matter of musical theater being a large part of who you are, but rather a large part of your time over many years went into this.
Sent you a private message.
I know someone who was accepted at Yale whose background as an a capella singer definitely helped. He went on to become a Whiffenpoof. Singing and theater is a big thing at schools like Brown. I would not hesitate to submit a supplement if you are good. Just make sure that it is a good recording. 
Perhaps contact admissions at Brown and be sure to find out the format in which they prefer to receive such supplements.