Best app so far – TwistedWave Audio Editor Review

I got this app in hopes of being able to add "epicenter bass" to songs which is pretty much boosting the lower end bass. I'm not sure if it's the app that just doesn't support splitting the track into 2 mono so I can only alter one. The way I add the effect is by lowering the pitch to -1200 cents and after that adding various low pass filters. It's great, but since I'm doing it to the whole song, I'm losing the highs which is the voice. Would love to find a way to keep an original version of the track played over the one I edited.
Review by Raul From Bartlett, TX on TwistedWave Audio Editor.