Audio sound masking

I have two audio signals, one is my environmental noise which acts as the maskee and another one is my ringtone which acts as the masker. I need to make my ringtone adaptive to the environmental noise, that is if my noise is loud, my ringtone will become loud, and if my noise is soft, my ringtone will become soft simultaneously. My approach to this project is to find the spectrum values of my maskee and the global threshold values of my masker, and make the max spectrum value of my maskee the same as the min threshold value of my masker. In this way, my masker will adjust accordingly and will also always be louder than my maskee. However, I'm not sure whether this approach is feasible. I need to do this in MATLAB and i have attached the codes for the psychoacoustic model to find the threshold values. I also have my audio signals. I have actually did my project halfway and have obtained the gain values that I need to apply to my masker. You should at least be able to help me apply the gain values to my masker and reconstruct my masker signal from the subband signals after applying the gain. Many Thanks.