Hi,
I have the voice trap V20 demo version installed in Audacity.
I have a music file loaded and voice trap open but when I select apply on voice trap it informs me that I must select audio in the project window?
Where do I find that option, is it in Audacity or the demo version of Voice Trap?
Thanks,
Martin
If you have a problem using Audacity, please always tell us what version of Audacity that is. See Help > About Audacity… .
To select audio in the project window, click and drag in the blue waves that you want to affect.
Audacity has Effect > Vocal Reduction and Isolation… by the way, but it cannot be used as a real-time effect that lets you change the effect parameters while listening.
Gale
HI Gale,
Thanks for the reply. 
That solved the problem.
I am trying to remove the backing but keep the singing part, I don’t think audacity can do that or am I wrong?
Martin
You still have not told us your version of Audacity. It’s important that you do that when you need help, or your reply may just be a load of “if” statements that take us a lot longer to write and you longer to read. 
If you have 2.1.1 or later, then you can use Vocal Reduction and Isolation to isolate centre-panned vocals. If the vocals are panned otherwise, you should continue to try VoiceTrap or other tools that use other methods.
Gale
Hi Gale,
Sorry. my bad, version 2.1.
I’ll have a try with the audacity tools.
Thanls for the help.
Martin
I am trying to remove the backing but keep the singing part
Note that these kind of effects are rarely “perfect”. They tend to be novelty effects that can be fun to play with but almost never useful in audio production or editing.
“You can’t u-bake a cake or un-fry an egg, and you can’t un-mix a recording”
If the vocals are perfectly centered (identical and in-phase in both channels) you can subtract left from right, and in that case the vocals can be completely removed (along with anything else in the center). And of course, you can completely eliminate the left or right channel (and optionally make a mono track that plays from both speakers).
All Audacity version numbers have three digits, so there is no “2.1” but there was a 2.1.0.
Gale
Hi DVDdoug,
Yes thanks, I understand that so it is now just getting to grips with this aspect of Audacity in order to see what I can achieve.
The idea is to produce just the vocals as far as possible then play the backing on my keyboard, that way I will be able to accompany my favourite performers.
Just for my own amusement and the fact that I cannot sing. 
Gale, yes you are correct it is 2.1.0.
Martin