Hi there, I wish to use the regain functionality of flac. To read samples from a wav file, I'm using the c library sndfilelib. This gives be samples between -1 and +1. I use the following code to establish the replay gain - #define BUFFER_LEN 4096 ... float data [BUFFER_LEN] ; InitGainAnalysis ( 44100 ); while ((readcount = sf_read_float (infile, data, BUFFER_LEN))) { int i; for(i = 0; i < readcount; i++) { if(i%2==0) l_samples[i/2] = data[i]*1.0; else r_samples[i/2] = data[i]*1.0; } int response = AnalyzeSamples ( l_samples, r_samples, readcount/2, 2 ); std::cout << "Response: "<< GAIN_ANALYSIS_ERROR << std::endl; } std::cout << Recommended dB change for song: "<< GetTitleGain() << "dB" << std::endl; which gives me a result of 64.82dB. If I multiple the samples by 10.0 (data[i]*10.0) and try again, I get the same result. If by 100.0 then I get 50.9dB, and by 1000.0 I get 30.9dB. Obviously having my samples in the range of -1 and 1 isn't working. What range should they be within. Thanks for your help, Barry