spaark
100+ Head-Fier
- Joined
- Feb 26, 2012
- Posts
- 111
- Likes
- 14
What is non-linear noise? What's the opposite?
Non-linear noise is noise produced by a non-linear system. If we're being pedantic, I suppose it's wrong to say the noise is non-linear, because it's the system that is.
I'm not sure I would use the term linear or non-linear in this context, correlated or de-correlated would perhaps be more accurate and less confusing. The act of dithering is the act of de-correlating the quantisation error, which is essentially just a fancy and more precise way of saying the errors are turned into random noise. If we're going into the finer detail, I'm not sure the last sentence I've quoted of yours is entirely accurate; generally noise shaped dither would actually slightly increase the total amount of noise but of course significantly decrease the amount of audible noise.
Less confusing (or rather more insightful) perhaps, because the correlation of quantisation errors is the reason behind non-linearity, but not more accurate. I'm just getting to the crux of the matter. The reason dithering improves fidelity is because it eliminates the non-linearity i.e. the distortion, which is much more audible than white noise of the same energy.
I think you're right than it slightly increases the amount of noise as far as real noise shaping techniques are concerned, but we'd like an ideal one to simply distribute it.