“How can I adjust the volume on the recordings I transfer from vinyl to my iPhone. The music I download from iTunes is louder than the music I transfer from vinyl. I am using EZ Vinyl.”
EZ Vinyl, which comes with the Ion USB Turntables, is a feature limited product with very little ability to do your vinyl record collection justice. My first suggestion would be to replace EZ Vinyl with Spin it Again. That doesn’t solve the problem of fixing the files you created already, but I do have a solution to that problem as well.
As long as the files you are recording with EZ Vinyl are MP3 format, you can use an app called MP3Gain to help normalize the volume between your audio tracks. You can set a target volume for a group of files with MP3Gain and the software automatically adjusts all the files to that volume. MP3Gain adjusts the volume in a non-destructive way, so you can revert back to the original volume if you need to in the future. You can add an unlimited number of files to the batch, making it easy to optimize a large number of files all at once. After optimizing the sound on the files, you can add them to your iPhone again, burn them to CD, or use them anywhere else and get consistent volume throughout your files. MP3Gain comes in both Windows and Mac versions.