Dear Jonathan,
We all, I believe, value your contributions to these forums.......I know I certainly do.
And I recognise that you must have vast experience in listening to audio systems of all types.
You should appreciate that most of to us here, also have many years of experience in listening to various systems belonging to other audiophiles as well as those in dealer's listening rooms and also hi-Fi shows so that our 'hearing' is conditioned by all those experiences and also more importantly, live music performances.
It is thus a little puzzling to think that you actually believe we are perhaps listening to distortions without somehow knowing it?
I have listened during a period of 2 years to a Rockport Sirius III turntable with your own quite good Olympos cartridge :^) and over the last 4 years, have regularly listened to a Continuum Caliburn with Cobra and again.....your modest Olympos.
I have heard hundreds of systems in rooms far far better than mine and have continually monitored my sound against all of these.
My room is not ideally designed with regard to equipment placement as you quite rightly point out but some of us have no other choices without a dedicated listening room.
One thing my room does have......is a wonderful acoustic volume with a ceiling raking up to a height of 18 feet. If you've ever heard what room 'volume' can do for your sound, you'd select that over most other parameters I believe.
My point is that the sound emanating from my system is compared to that of the finest sources, amplification and speakers commercially available and I believe that I can detect 'distortions' as well as you or anyone else.
The greatest changes I've heard to my sound over the last 2 years is in fact in the reduction of distortions from the turntable.
Some of this results from the isolated armpods (I do still play the Raven AC-3 for comparison) but the major reduction in analogue distortions to my ears, has been the switch to MM cartridges over LOMCs.
I can hear high frequency distortion in most of the LOMCs regardless of the arm, turntable or set-up.
Now you obviously do not hear these distortions so I'm not sure that a meaningful discussion between us on that topic is achievable :^(
Having said all that......there are those who prefer DD to Belt Drive and others who prefer Idlers. As I've said before.......I find far greater differences in cartridges than in drive type and I admire those who claim to hear those differences.
I can't stand the distortions I hear in digital reproduction yet most here, can happily live with them?
We all are different and all our experiences are valid.
I've also learnt that 'blanket' statements regarding audio are commonly wrong?
This is a 'discussion' Forum and the more we have.....the more we can possibly learn.