Hi, there are many audiophile claims to hear differences between different manufactured pressings of a CD which contain the identical bits or of CD-Rs that contain identical bits.

I am aware of the Prism study from 1996 which showed that 50 listeners were unable to distinguish CDs manufactured in different ways from each other (and found the placebo disk one of the most if not the most "different" sounding from the identical reference disk).

However, if someone believes in disc-dependent differences, they could dismiss that study on the basis of the paper labels on used on the disks or on other uncontrolled "variables" like static charge etc. (Not to mention the flawed experimental design which asked for a rank order of differences instead of a simple two or three point scale of same/dif or same/little dif/big dif). So--better than nothing but not great either.

I've come here to ask the expert. Are there any disc-dependent effects--the quality of the pits, SHM/blu-spec materials, the eccentricity of the disc, the cleanliness of the surface, static buildup, magnetization, cryogenic treatment, painting the edge, the art printed on the label, gold vs. aluminum, that have or could have a direct effect on the sound without affecting the integrity of the data?

Note--by direct I mean to exclude a secondary effect such as effects on the power supply which might have repurcussions on the clock or the audio circuits if they are not properly isolated.

Thank you in advance.