Turnable database with TimeLine

Studying the video of Syntax's RX-5000 turntable with the Timeline.....I was trying to analyse the reasons for such a poor performance?
Mainly because I had seen nothing like it with any other turntable...belt-drive or direct drive?
How could the Timeline laser move backwards at every revolution and by the third or forth one.....jerk erratically forward to where it originally started?
And suddenly I understood.....here was a perfect visualisation of motor cogging.
This Micro Seiki motor was cogging its head off......spitting and spatting like some rat attached to electrodes?
No wonder Thuchan threw out his Micro motor and replaced it with the VPI one for his RX-5000....and sold off his SX-8000II with Micro motor?
Thuchan has discerning ears and can hear the comparisons to his EMT927 and Continuum Criterion.

And was I the only one to hear the 'sound' on Syntax's video?
I know it's compressed and running through an iPhone mic......but so are mine?
And what about the 'scraping' noise that appears half way through?
As Syntax is want to say....."one man's mountain is another man's valley"....

Halcro, I just rewatched Syntax's video of his RX-5000. To be fair, I think the frame speed of his video camera is interfering with the laser flash increments. I think that is why some laser flashes are not even seen and why the dash appears to change in length. This occurs with my iPhone video as well, but to a lesser degree. I don't know the f/s spec. for the iPhone.

I think the scratching/rubbing sound to which your refer is his breathing. Inhale, exhale etc.

This thread is supposed to be a database for Timeline results and if each submitted video is criticize to the extent that you criticize Syntax's video, few members will be encouraged to add to the database. One of the problems I see with this format is that it is hard to find the videos if the links are added somewhere down the thread, but I don't see how this can be changed now.

Hi Halcro, let me explain something about motors here without the added detail of charts and graphs. A motor runs at a constant speed to the casual observer; but if you take a much closer look you would see that the motor armature actually speeds up and slows down as it passes by the individual poles. Cogging is an accentuated aspect of this motor property. A flywheel is added to the armature to smooth out this periodic motion. This is a property of any motor type. Now, with the exception of DD turntables, the motor is just one part of the platter drivetrain. If the pulley on the motor shaft, or the idler as the case may be, is not perfectly centered then the pulley will add a periodic motion. The roundness of the pulley and of the platter where the belt or idler rides as well as the eccentricity of the platter contributes to this periodic motion. So just like a record that has an off center hole moves back and forth during play, the motor pulley and platter are doing this too; but hopefully at an almost undetectable amount. Therefore, the motion of the platter- any platter is not perfectly constant during a single rotation. Being periodic, meaning that it slows down and speeds up, it can still hit the 1.8 second mark every time because the average speed is 33 1/3. You can see an eccentric record moving back and forth during rotation causing the tangential speed at the stylus to vary. The record is still spinning at exactly 33 1/3; but if it is off by a good amount then the WOW can be heard at every peak of rotation. That goes back to my motor analogy- you can speed up and slow down your car between mile markers and still have the correct average speed.

One other thing: Look at the specs of most turntables. The WOW & Flutter measurements of most high end tables all seem to be around +/-0.02% to +/-0.04%. Most of these very nice turntables here are showing excellent speed settings to within 0.00X%. It's clear that many companies have come very close to perfection with regard to speed control. WOW & Flutter numbers do not seem to vary much among competitive tables which is I believe due to limits of machining tolerances. WOW & Flutter being the periodic motion of the platter that I described.

Thanks Halcro. As a fellow Raven user I appreciate your feedback. I have a strobe disc that allows active adjustment while playing so I'll add a small amount of compensation.
Best regards,