If you're looking to do audio, you'll want something beefy like a Raspberry Pi or BeagleBone. I've not actually checked this, but do see if Bass (un4seen.com) works on one of those distros as it will make your life infinitely easier.
An Arduino or comparable board isn't suitable for audio unless you have very minimal requirements, e.g. play a bell/buzzer or cheesy "tink tink" sounds. I've had my Arduino playing different songs, like the Empire's theme from Star Wars, but it's "tink tink" and every single note has to be programmed. Fun? Sure. Productive? Not so much.
But there are other boards out there that are much beefier than a Pi. They're also more expensive though.
What I'd recommend is having a browse around to see if there are any similar projects for what you want, or anything of comparable magnitude, e.g. CPU requirements, memory, speed, power consumption, etc. That will let you see what others have already done. If they have Youtube videos, all the better as you can then see the performance as well.