Or you can get a try Coolmuster iPad iPhone iPod to PC Transfer software.
Like :
http://www.coolmuster.com/idevices/transfer-music-from-iphone-to-computer.html

You can get more information from these methods:

Method 1: Using iTunes

1. Connect your iphone on computer.

2. Open up the iTunes, and synchronize iTunes with iPhone.

3. Transfer music from iphone to iTunes, then to computer.

Method 2: Using iCloud

1. Set up icloud both on iphone and computer.

2. Sign in the icloud with the Apple ID

3. Start to sync iphone data to icloud.

Method3: Using Coolmuster iPad iPhone iPod to PC Transfer software

You can try Coolmuster iPad iPhone iPod to PC Transfer software to transfer iphone music to computer directly.