...you're using it? My ISP recently decided to cut off anyone who downloads music illegally, not that I ever would, I'm just a curious geek! If you were to use bitorrent through a proxy server, can your ISP tell that you're using bittorrent?
If it’s a simple proxy, they may be able to see what you’re transmitting.
If you’re using an encrypted VPN, then they would only see that you’re using a VPN and not the contents of the transferred data. Still, they would see the amount that’s being transferred because they are still the ones that provide you your connection to the internet and transmit to your computer all the data involved.
So you can use a VPN to download illegal music. You can visit IP-Details.com to ensure that the VPN is enabled.