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Does DITHER explain Analog vs Digital preference?

I came across a CD Digital track with a synthetic added hiss and pop like a turntable. It was added by the sound engineer for "effect", however, it still sounded remarkably good. The hiss and crackle background noise seemed to make the music stand out even further than usual and gives it a life-like real world feel. This may be analogous to a contrasting frame around artwork that enhances the colors within the painting/photo.

I looked through my collection and I have at least a dozen CD tracks, usually pop music, mixed with intentionaly added wideband background noise. These all sounded good... although the higher background noise can be annoying if you allow yourself to focus on it.

This lead me to thinking about how a significant number of audiophiles prefer Vinyl or Analog sources over Digital: Would the Analog audiophile enjoy these "noisy" CD's more than a conventional CD mix with a very low noise floor?

Following this logic leads to a possible explanation for some peoples strong preference of noisy Analog over the technology of Digital.

Could it all be in the DITHER?

In Digital signal processing a technique called "dithering" is used to improve the accuracy of the signal. The idea is simple....a low level of high frequency noise is added in order to improve the accuracy of the conversion of the primary signal. The high frequency noise, which is outside the audible band, is later filtered out in the processing chain, leaving only the more accurately converted primary signal.

It seems plausible that a small level of background noise might actualy raise the ability of listeners to perceive certain low level details within the music. Without this added noise then some of the low level detail simply falls below a threshold of human perception and goes unnoticed. In an analogy to Digital processing, the human brain might actually extract the low level detail from the noise by performing the final processing step of stripping out the wideband noise; the listener simply "focusses" on the music.
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Showing 1 response by lp2cd

lp2cd
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The phenomenon shadorne alludes to in the first post from (only!) 10 years ago is generally known as "stochastic resonance." It’s a very real phenomenon that occurs in analog and natural biological sensory systems, including human audition. Broadly defined, "Stochastic resonance (SR) is a phenomenon where a signal that is normally too weak to be detected by a sensor, can be boosted by adding white noise to the signal, which contains a wide spectrum of frequencies." It applies to other sensory systems besides hearing, including taste and olfaction, as well as electro-mechanical sensing systems such as sonar. See:

https://en.wikipedia.org/wiki/Stochastic_resonance
*and*
https://en.wikipedia.org/wiki/Stochastic_resonance_(sensory_neurobiology)
*and, if you REALLY want to dive in deep,*
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2660436/

So yes. it is possible that some people may indeed find their listening experience enhanced by at least a certain low but audible amount of surface noise from an LP. Dither might be considered in some senses to be the digital analog to analog stochastic resonance. In practice, however, they are functionally rather different, dither being applied at a very much lower level.
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