Way back when I used a piece of HP equipment to measure distortion of a sine wave. It was fun to use, but long gone.
How would a hobbiest measure distortion of a sine wave? It can look good on a oscope and still be pretty bad.
One thought is to take the waveform in question, filter it though several low pass filters to create a reference (without phase shifting it), invert it, and null it with op amps. What is left is the distortion.
Anyone seen a home brew setup to do this? With all the audiophiles out there I suspect it exists.
How would a hobbiest measure distortion of a sine wave? It can look good on a oscope and still be pretty bad.
One thought is to take the waveform in question, filter it though several low pass filters to create a reference (without phase shifting it), invert it, and null it with op amps. What is left is the distortion.
Anyone seen a home brew setup to do this? With all the audiophiles out there I suspect it exists.