Speed Stability

I noticed while playing records over the past week that the European and Asian pressings seem to be punched true-ie. no visible swaying of my tonearm. US pressings however, seem to be a mixed bag. Some records are true and some I see the tonearm swaying quite a bit. Still, with the exception of the pure test tone section of my test record, I cannot hear the runout in the music.

After reading these posts the last few days, it got me curious to see how stable my Sota turntable speed is based on listening tests and using the strobe disc. I have a stereo test record so I put that on the platter and then my Sota strobe disk which I clamped down onto the record. I have a 4 inch plug-in fluorescent light that makes a good source for the strobe disc. First, I started the turntable with the tonearm up. I locked in on one rectangle on the strobe disc and noted that it stayed in place for several record rotations. Rock steady stable. Next, I cued the tonearm on the outside lead-in groove of my test record and then locked onto a rectangle again on my strobe disc. As the tonearm dropped onto the record I saw no drift of the strobe disc rectangle. Still rock solid steady. I then played the pure test tones on my test record, 440Hz, 1000Hz and 3150Hz- specifically for flutter measurements. To me and my son, these tones were all steady in pitch. But what we both heard was a periodic shift in the image from center to slightly right. So I go to the turntable and get down eye level with the tonearm and I see the tonearm swaying from left to right. Conclusion: My test record has runout. The hole is slightly off center. I see this same issue on several of my records. So my question is: If the source material has some amount of runout, at what point does spending kilo-dollars for better speed stability yield little to no results? Based on my observations and measurements of my Sota here, what am I missing/overlooking?

I want to think that some labels did a better job of centering the hole in albums than others. I am almost curious enough (but not quite) to measure the hole position of a group of records to see just how far off they are and how much they vary. Maybe someone has already done that- perhaps even by label so we could all know which ones are better for critical listening.

Then it would stand to reason that the position of the record relative to the platter can affect playback quality. What I mean is, if the turntable has a certain rhythm (wow and flutter characteristics) then it must be possible to turn the record relative to the platter, ie say in 10-15 degree increments and effectively match, or optimize the record's eccentric hole tolerances to your turntable and find the best playback position. Sounds like an interesting experiment. Has anyone tried this?

We are well beyond eccentric platters here. The experiment is based upon matching the noticeable to unnoticeable eccentricity of the source (the record) to the wow and flutter and surely the unmeasurable runout of the turntable platter. The theory is that a record should sound better at the optimum position relative to the platter. Has anyone ever noticed that sometimes a record sounds really good and at other times just so so? Could it be related to the record's random placement on the platter?