I found an article that addresses this question specifically
here
In it a chart of research results over 60 years is given & the lowest JND is 0.25dB F.E. Toole and S. Olive, "The Modification of Timbre by Resonances: Perception and Measurements", JAES vol 36, # 3, March 1988, pp 122-142
The author states "Toole and Olive, on the other hand, in their 1988 study used pink noise for their acoustic signal source and determined that a 5 kHz resonance, with Q = 1 was just detectable at .25 dB." But later "The .25 dB figure quoted from the Toole & Olive research seems to contradict this (his JND of 0.75dB or 1dB), but consider the filter Q = 1. That's a pretty broad chunk of the audible spectrum over which that resonance exists. With the ear-brain combo performing an integration across that broad a portion of the audible spectrum than its easy to see how a large amount of acoustical energy is captured, leaving a change that small noticeable. However, pink noise is not real world and one thing my research has shown is that the hearing process reacts very differently to different types of sound; a .25 dB detectable difference using real music just isn't plausible and the research supports that."
He goes on to state "In this particular article, I settled on a minimum discernable difference dB value of .75 - 1.0. My experience has shown that this is what the average listener, under average listening conditions, listening to music played back through typical consumer-grade audio gear will be able to clearly identify - and do so repeatedly."
So, I'm still looking for any research which backs up the claim that 0.1dB amplitude difference is noticeable as a quality difference when playing music? Any links, ESL?