How do we best set up forms and recordings (mp3)?

We would like to use your service for our annual Southwest Honor Band and Orchestra online tryouts.  We want the informational form to have a place to accept mp3 recordings (2-3 minutes long max each).  We are looking at about 400 entries.  How would we go about setting this up properly? 

Thank you so much

We have this Voice Recording widget that would allow you to records audios in the form. 

https://widgets.jotform.com/widget/voice_recorder

The result is however in .WAV format.

Here's how you can add a widget in your form:

https://www.jotform.com/help/252-How-to-Add-a-Widget-to-your-Form 

If you'd like to accept MP3 file upload, you may consider creating a file upload form using our default file upload fields. Here's our guide on how you can create an upload form: https://www.jotform.com/help/332-How-to-Create-Upload-Forms. 

Now, free accounts are only limited to 100MB of File Uploads (fixed) and 100 monthly submissions. You may consider upgrading to increase the limits.

https://www.jotform.com/help/331-How-to-upgrade-my-account  

Let us know if you have any further questions.