Erik, > Notice that step where you throw away the middle N/2 samples? > That is a low pass filter applied in the frequency domain. Not if the amplitudes are all already zero above N/2. In that case, the input and output frequency spectra are absolutely identical. If nothing was removed or even altered, then no filtering has actually occurred. A similar situation is what I have previously stated as my starting assumption. > Less accurate how? Is this measurable or is this just hand waving? I have already addressed this in previous postings where I described the fact that I had merely listened to the recordings repeatedly until I could distinguish the original from the sndfile-resample one and could not distinguish the FFT-overlap one from the original --- ergo less accurate. My intention was not to "measure" accuracy, but to listen for the alleged distortions. You had posted a sort of celebration of the fact that I thought the sinc-based resampler produced a better-sounding version of the recording than my FFT-overlap resampler, but apparently had also neglected the fact that I was also saying that it sounded better than the original --- ergo was inaccurate (albeit very, very slightly so). I was merely attempting to correct possible misunderstandings. Now I could take time to measure my resampler's performance, but I think we both know the expected results, don't we? In terms of absolute accuracy, any FFT-overlap resampler which utilizes large windows (hundreds of thousands or millions of samples) and which is properly implemented should, in fixed-rate conversions, outperform a sinc-based resampler that has been localized in the manner that Smith has developed for the very useful purpose of allowing variable-rate conversions. However, the difference may be measurable but not audible, hence of questionable utility. Best regards, Dave. P.S. I'll be "sans computer" for the next few days, heading towards Ivan so won't be able to correspond on this for a while....
