So Weird- No Stylus Contact Woofer Pumping with Hana ML and Elac PPA-2

@lewm  - on the high pass filter, I asked the OP about that in an earlier post and he did say it was engaged in all his tests - the response was:

"The weird thing is that the hi pass filter works, I have some real nasty LP’s that rumble and the filter knocks it out. So your guess is as good as mine. Also the pumping was worse with the filter off- real audible bottoming out stuff."

Also, in the video you can see it is on - the PPA-2 shows that on the front panel (4th LED from the left).

I watched the video again in the beginning, and the woofer excursions are not uniform - two large excursions (I think), followed by a higher speed flutter of smaller excursions before a very brief rest and then it starts up again - the whole sequence at what appears to be once per revolution. However, this might not mean the static is unevenly distributed on the surface - it could be this is just how the PPA-2 or the 851A integrated reacts to what seems like input overload.

I still wonder if that with the XLR connections, and the PPA-2’s different grounding scheme separating tonearm and chassis ground, that the static has no where to go but through the signal path and get amplified. With the RCA connection, the static can get to chassis ground via the RCA shields (assuming those are connected to chassis ground - they usually are) and then can dissipate through the IEC outlet and not get amplification.

@ejb14

The cable set is not a coaxial design.

The cables are the same in both RCA and XLR configurations. The cable itself is a star quad core with double bare copper shielding.

With RCA attached, the positive signal is using, say the 12 and 6 o’clock wires. The negative signal is using the 3 and 9 o’clock wires. The shield floats at the TT end and is joined to the negative wires at the RCA collar joint. The positive is joined at the pin.

In XLR configuration, positive attaches to Pin 2, negative to Pin 3, Pin 1 is vacant and the shield is attached to the shell. The shield is floated at the TT end.

The tonearm ground handled by the external ground wire in both cases.

The idea that the ES charge is concentrated at one area on an LP or on the mat is contrary to data collected by Shure Corporation, when they studied ES charge in vinyl reproduction, albeit many years ago; they suggested that charge distributes evenly across an LP surface.  However, I could perceive that there might be some assymmetry to charge distribution due to fingerprints or other oily or watery deposits on the LP surface.  So perhaps the data you cite would contradict their earlier findings.  I will take a look. 

How does a static charge and electric field manifest itself in the signal?

And we still have not had an answer as to whether the 18Hz high pass filter on the preamp was engaged during all of these investigations.  If it was engaged, then I would expect there to be little to no woofer pumping when the platter is spun at speeds below 18Hz.  Yet I thought the OP reported he can spin the platter by hand at speeds well below 33 rpm, and still visualize the phenomenon.

If it was say the magnetic field from a Hall effect sensor or the motor, then as long as the thing is localised to a small fraction of a rotation, then it will appear like >18Hz.

In XLR configuration, positive attaches to Pin 2, negative to Pin 3, Pin 1 is vacant and the shield is attached to the shell. The shield is floated at the TT end.

^As you have said^… that is pretty much the main difference, and hence why I suggested that you could try attaching Pin-1.

It’s static. I converted back to balanced operation and wet cleaned a few LP’s. Problem gone. I have an Ionizing fan on order and we’ll see how that works.

I think the reason the rumble filter doesn’t stop it is that it’s DC with a slow rise time. The o-scope looks hilarious.