MP3 High Frequency Reconstruction Help 2021-01-04 13:28:36 I have been trying to perform efficient spectral enhancement to convert low bitrate MP3 files to high bitrate ones using Machine Learning techniques. I have been successful in recreating a good part of the audio spectrum as seen below in the image (Showing 80Kbps vs 160Kbps vs Upscaled 80Kbps to 160Kbps). My problem here is that the reconstructed audio still doesn't sound any different from the original 80Kbps file inspite of decent spectrogram, phase and magnitude spectrum plots. I did plot the magnitude squared coherence estimate of the upscaled and the high bitrate audio and the graph isn't even close to being what I had expected (a flat line plot of an array having all ones).Could this be the reason for the reconstructed audio to not sound the same? If so then is there any way to convert the scipy coherence function to a differentiable function which I can optimize on and get better results or perhaps a different function to optimize coherence? My current scores are as follows:MSE between the high kbps and upscaled STFTs (Unnormalized)= 0.07 SSIM score = 0.0024MSE between magnitude spectrums (Scaled)= 3e-9MSE between phase spectrums (Scaled) = 0.008At this point I am extremely confused as to what I could do more to make them sound similar. If you wish to hear the above two second sample then I have attached the three files below. Some advice or guidance would be really helpful. Thanks in advance!