My first Sony player used an analog 'brick wall filter' to remove the digital artifacts above 20 kilohertz. These filters worked fine for frequency but suffered from abysmal phase response. As the frequency approaches the sharp cutoff of 'brick wall' filter, the energy takes longer to get through the filter. This is akin to the trebles coming out of the filter after the music stops. You are not supposed to hear these small delays so why did those players sound so terrible?
Well, did they all sound terrible? It was not an opinion shared by everyone other than a rather small contingent and some of those were and still are Luddites.
Laying around somewhere in my house, and god knows where, there's an old player which I'll try and find do some comparative listening. However, consider that way back when there are other reasons why stuff may've sounded 'terrible'.
1) How it was mastered. IOW many applied similar techniques used in vinyl reproduction to this new medium.
2) Practically speaking, vinyl is a medium that has a far smaller bandwidth, greater noise floor, varying levels of distortion, crosstalk issues, less dynamic range, and a bunch of other things that CD simply doesn't have. Well, CD does have it if you make a digital recording from your vinyl, but that's another matter. Frankly, people who heard the "same"
two recordings on vinyl and CD literally heard two distinct and different presentations, with CD quite potentially revealing information that wasn't audible on vinyl. Not everyone liked this and frankly invented all sorts of techno and pseudo-babble to rationalize their preference. Further, if these phase characteristics were so objectionable, why are they not objectionable in the following scenarios?
a) Examine some of the phase errors in many tube based amplifiers.
b) Consider the phase errors that are introduced in the recording process.
c) Phase errors are rather signficant with phono cartridges.
In a general sense HIPAR, I do though agree that some early, non-oversampling had issues with both the anti-aliasing and anti-imaging filters. Given the inherent variances in manufacturing, desire to saturate the market, and ignorance, spending more on or designing technically better performing analog based filters didn't always happen. Moving to oversampling and allowing the bulk of the work to be done in the digital domain made life easier and costs cheaper.
A couple of decades is a long time though. Might not be a bad idea though to hold on to older units given the way DRM is being pushed by the recording industry and legislated by those who need 40 pieces of silver.