Reconstructing the song using its dominant frequencies I have found out 20 dominant frequencies of a song by splitting it into 20 sound-clips and applying Fourier transform on each one of the sound-clips. Now I am trying to reconstruct the song back from these 20 dominant frequencies.

info_ = audioinfo('../wws.wav'); % 11 secs long song

Fs = info_.SampleRate;
chunkDuration = 0.6; 
numSamplesPerChunk = chunkDuration*Fs;

freq_vec = [];
for startLoc = 1:numSamplesPerChunk:info_.TotalSamples  
    endLoc = min(startLoc + numSamplesPerChunk - 1, info_.TotalSamples);
    [x, Fs] = audioread('../wws.wav', [startLoc endLoc]);
    x = x(:,1); 
    dt = 1/Fs; 
    t = 0:dt:(length(x)*dt)-dt; % time scale
    L = length(t); 
    nfft = 2^nextpow2(L);
    y = fft(x, nfft);
    y = abs(y.^2); 
    y = y(1:1+nfft/2); 
    [v,k] = max(y); 
    f_scale = (0:nfft/2)* Fs/nfft;
    freq_vec = [freq_vec, f_scale(k)];
end


freq_vec is the vector of dominant frequencies of the song. My question is how can I use these frequencies to build back the song.
Short answer: You can't.

Sound is more than its dominant frequencies, and you threw away anything but that.