How to format a tag using text from the same tag

Hello all,

I have a long list a albums from a audio series that look like the following: "01_album name" and trying to make them look like the following "01_album name(Vol. 01)". I clicked on actions and "Replace with regular expression". Field is ALBUM, Regular expression is: ^(\d\d), and Replace matches with is: %album%(Vol. $1). When use the Action, I get: %album%(Vol. 01)_album name. Am I going about this all wrong or is there something I am not seeing here.

Thanks,
daring_t

Try:
Search pattern: ^(\d\d)_(.*)
Replace with: $1_$2(Vol.$1)

That worked perfectly! That's exactly what I was looking for. Thanks ohrenkino!