Mass rename of files replacing '_' with space

[jessexoc]

How do you mass rename files from the command line? I have a bunch of mp3's with filenames like:
Artist_-_Album_-_TrackNumber_-_Track_name.mp3

I want to convert all the "_"(underscore) to " "(space). I tried:
$ for i in *; do mv "$i" `echo $i | tr '_' ' '`; done

but it complains that:
mv: target `name.mp3' is not a directory.

What am i doing wrong?

[richiefrich]

I got's two you can try
for i in ./*.mp3; do mv echo "$i" "${i//_/ }"; done
if the output looks ok, remove the echo

OR
pipe this --> sed -e 's/ /_/'

kinda like this
find /mp3 -iname '*.mp3' -exec echo "$i" "`echo $i | sed -e 's/_/ /'" \;

[CodeRoot]

Try:

$ for i in *_*; do mv "$i" "`echo $i | tr '_' ' '`"; done