Hey there,
I have a rather complicated design that uses, among other things, a comparison of LOG functions on L and R input audio, that is turned into a value used to scale the output audio on both channels.
The trouble is, when the two signals coming in are approaching a peak in the audio in the same direction at the same time, the numbers start to get smaller, and because the log approximation is only good to..I think it's 0.0125? increments, one of those values changes in quite a digital manner before the other, instead of a smooth increasing transition that would come if the log had more resolution.
The sum total of this is that the audio output that is being moderated by these numbers jumps up and down in 0.3dB increments in places where it should just be a smooth transition - this happens on the upper/lower ~10% for most if not all peaks, for anywhere between 1 and ~15 samples at 48Khz, and is then quite audibly present in the output audio as a pop/crackle distortion in the center of the stereo.
I considered using the reciprocal instead of log to create a divide function to achieve a similar result, but the reciprocal only works for values b/w 0.1 and 1, and seems to be quite useless for audio as a result.
I've verified that it's the low-precision logarithm that is responsible for my problem - I'm just wondering if anyone knows how to increase the resolution or create a more precise log function for the TAS3204.
I'm not an expert in DSP by a very far cry, but this is a strange one to me.
Cheers
David.