Okay, five controllers are not now the world. You can make rough adjustments, which sometimes represent a real improvement, but everything can be so not natural tear. And the Kindle Fire HDX 8.9 of unaltered original sound is often better by far. Why I find extremely useful the Bypass button. So I can choose an ad hoc basis, if I turn the equalizer off or wants. (Who by the way does not detect a tonal difference when you move the controller, I put my heart, turn the bypass function!) On my Kindle Fire HD 7 I use the Best Sound EQ often - as I said, fine adjustment is not in it, but since I had the 99 Coins left, it was worth a try (I would like to see more control!). For the price the app is fine