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

I wonder what would happen if you changed cartridges. Both the mat and the record elevate the rotating surface toward the suspended stylus. Every rotating surface has son "fan" effect and may air currents around the stylus and cantilever.

Put both the record and mat on the table. Using the lift what does stylus elevation do to the intensity of the pumping. With the stylus suspend over the spinning record carefully slide a piece of cardboard over the surface of the record holding on to it. What happens to the pumping. Air currents could be interacting with the unloaded resonance of the cantilever's suspension?             

70% of people are stupid. Fortunately, I'm in the other 40%.

@ejb14

1. Isn’t woofer pumping caused by infrasonic frequencies (below 20hz)?

Yes it is

2. The PPA-2 has a rumble filter and I believe that I saw it turned on when the woofer pumping is occurring - doesn’t a rumble filter filter out these frequencies precisely for this reason - to prevent large woofer excursions?

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.

3. Not sure how static would cause the cartridge to output signal in the infrasonic range. Even so, the Funk Firm mat claims to be static free, yet with just that mat on the platter still exposed this issue; so if not static, then what?

I’m still all in with team static, until a more likely explanation is revealed or Peter Madnick see’s this and can explain it.

 

Attention Deficit Disorder? You’re probably just noticing it because you weren’t paying attention before.

OP - Thanks for your indulgence. Think I may be developing ADD in my old age (turned 70 in Jan). Totally missed your original post.

As for the problem, damn that's weird! Got to have something to do with static elec/low humidity.

Thanks again. 

A few questions;

1. Isn’t woofer pumping caused by infrasonic frequencies (below 20hz)? A John Atkinson quote from 2009 Stereophile seems to support this, though he was referring to record warps in that quote;

https://www.stereophile.com/content/bass-cone-flap-1

2. The PPA-2 has a rumble filter and I believe that I saw it turned on when the woofer pumping is occurring - doesn’t a rumble filter filter out these frequencies precisely for this reason - to prevent large woofer excursions? If so, it would seem the rumble filter is not working on this phono stage - you may want to look into a warranty repair if we can assume the woofer pumping is being caused by infrasonic frequency.

3. Not sure how static would cause the cartridge to output signal in the infrasonic range. Even so, the Funk Firm mat claims to be static free, yet with just that mat on the platter still exposed this issue; so if not static, then what?

Take a look for yourself

 

Any way this could have something to do with the 6db boost in balanced configuration compared to the single ended?  Does the woofer pump in balanced mode if the speaker is much farter away from the table?

as per previous post 

A- Pumping exists when the system set up is: Balanced output from tonearm to balanced input at phono preamp and:

1. Stylus is over the play surface and the platter is rotating- not off to the side (it also persists with the stylus on the record).
2. There is a just a record on the platter (rotating)
3. There is a just a mat on the platter (rotating)- the mat is a synthetic material.
4. There is a mat and a record together (rotating)

B- Woofer pumping stops when:

1. There is platter rotation and the platter is empty, no record, no mat
2. There is no rotation regardless of what on the platter.

Results

Yes

Have you tried putting the record on the metal platter (without the record mat)?

How 'bout the mat with no record?

At least you'll isolate the offending object.

@fsonicsmith I thought that if I got continuity from cartridge white pin to XLR L pin 2, blue to L pin 3, red to R pin2 and green to R pin 3, and if George Cardas welcomed to the right channel on the right side and in phase was in the middle I was pretty good. What did I miss?

Uh, see my previous post. You can still try it and report back. I suspect the problem goes away when you remove either the record or record and mat because the spinning magnetically charged item (record or mat or both) excites the improperly connected cartridge whereas the aluminum platter does not.

Wiring for the tonearm to the preamp was as follows:

• Pin 1- no connection
• Pin 2- + positive
• Pin 3- - negative
• Shell ground- cable shield

Why was it wired like that? I agree the typical connection is pin 1 for the shield. See excerpt from the Elac PPA-2 Manual:

"Typically a balanced connection will be more immune to hum, so it would be the preferred connection. However, you must be careful that the shell of the XLR is not connected directly to the ground line within the XLR connector ( That sentence is a little confusing but I take it to mean that the shell of the XLR should not be connected to pin 1). They SHOULD be independent. The shell is the external shield of the cable and connector, and should be the CHASSIS connection. The ground wire within the XLR is twisted with the (+) and (-) balanced and should be the signal or tonearm ground. This can all be confirmed with an Ohm meter. "

The PPA-2 has two ground lugs, one for tone arm ground (labeled ground) and one for chassis ground (labeled chassis). Since there is no chassis ground on the GT2000, that lug remains unused. The tonearm ground is connected via the other ground lug.

The cable shield is NOT connected at the TT end, but is connected via XLR shell to the chassis ground.

 

 

Good find, Dekay.  For a true balanced hook-up from cartridge to a true balanced phono stage, audio ground is typically floated (no ground, in other words).  Pin2 of the XLR connector is typically connected to the positive phase ("hot" on an RCA connection), and pin3 carries the negative phase (the outer barrel of an RCA).  Pin1 can be connected to shield but not to the cartridge. Maybe there is a wiring problem that only pertains when operating in balanced mode. But I hate to say this, the video shows the problem goes away when LP and platter mat are removed, even though he is still (I think) operating the system in balanced mode at that point. If we can throw out that bit of information, it makes more sense. (Just kidding; we are stuck with the facts of the matter.)

Has anyone here read the OP's previous thread?

 

DeKay

I also had a Zerostat in the seventies. Seems to me, it was four or five times stronger than the current ones. They used to use some kind of radioactive element which came with a warning to keep away from your children.

@dweller , I had one of those when I was a teenager back in the late 70's, it's funny to see it again. So funny I'll have to buy one- again.

Let’s review,

Woofer pumping is tied to rotation speed, the pumping is faster at 45 than 33 also spinning the platter by hand will excite the woofers.

A- Pumping exists when the system set up is: Balanced output from tonearm to balanced input at phono preamp and:

1. Stylus is over the play surface and the platter is rotating- not off to the side (it also persists with the stylus on the record).
2. There is a just a record on the platter (rotating)
3. There is a just a mat on the platter (rotating)- the mat is a synthetic material.
4. There is a mat and a record together (rotating)

B- Woofer pumping stops when:

1. There is platter rotation and the platter is empty, no record, no mat
2. There is no rotation regardless of what on the platter.

B1- Disproves the magnet in the platter theory. Also the platter is hot forged and is as close as humanly possible to 100% pure aluminum. There are no ferrous metals involved.

Static electricity is just that static, hanging on for as long as it takes to discharge to an object of lower potential. I believe it’s widely accepted that vinyl records are able to hold a static charge. So I’m all in on that.

@nrenter I’d be interested to check the humidity of your house-

25%RH right now.

if you wet-wash or simply dry brush your records, etc.

Wet wash occasionally, dry brush prior to use.

Did the single ended connection really solve your problem?

Yes

Did the rewiring create a better ground path?

Ummmmm... maybe? I just check continuity and move on.

Why do people feel the need to comment without watching your video?

I don’t know, it’s annoying.

@lewm The issue with the pumping occurred over a period period of days and the video shows only the effect and it’s current solution.

To me the bigger question is about the implementation of balanced phono output overall. I was pretty eager to try balanced output in my system for it’s obvious benefits, 6db boost over single end, inherent in system noise reduction etc. I was not expecting to see a whole new problem surface.

I would really be interested to hear from anyone with a balanced output system as to how their experience is going.

It’s possible this is one reason so few phono preamps offer this feature. I know Project has a whole program for balanced TT’s. If so, I’m guessing they have incorporated solutions to situations like this.

There could be a simple wiring fix to this.

I will be looking into static control and once I have some tools on hand, I’ll probably attempt the Balanced output experiment again.

 

 

He’d have to reinstall the XLRs and switch to balanced mode on his preamp in order to revisit the problem, and he prefers not to do that. So further conjecture is futile.

@mitchellcp , I missed that part. Very interesting. Is it the stock mat? Did Yamaha put the magnet in the mat?? Take any old magnet and scan the mat with it. 

Right, you are using a Funk Firm mat. Take a movie of the pumping take the mat off and put it on up side down see and take another movie, see if the rhythm of the pumping remains the same. 

You might also check with Funk Firm to see if there is any metal in the mat. There could be metal fibers (steel wool)  in the mat to remove static from the record. 

The answer to static...

 

I’m voting on static buildup. The filth on your records is the tell. I’d be interested to check the humidity of your house, the carpet (or rug) between your record storage and turntable, what kind of shoes you do (or do not) wear, if you wet-wash or simply dry brush your records, etc. I’m assuming whatever you are doing before putting the vinyl on the platter is leaving one heck of a charge on your record. The other questions remain: Did the single ended connection really solve your problem?  Did the rewiring create a better ground path? Why do people feel the need to comment without watching your video?

I looked it up it’s 5.8kg or 12.87lbs

The two holes on the platter are threaded so you can attach a pair of removal bolts- it’s ridiculously heavy.

This one is a pickle, to be sure.

I wonder if this table has a signal cutout mechanism that detects when a record is on on or off the platter and shorts the output when there is nothing on there? My Dual 701 has a signal cut mechanism, but used differently - it cuts the signal when lifting at the end of a record or when auto-starting. The point is that some turntable manufacturers have thought to prevent outputs in certain conditions and Yamaha has done this with some of their tables. I don't know if they did it for this one. What are the two holes in the platter for I wonder?

You could test this without changing the interconnect plugs. Just put your stylus over the spinning platter and use a stylus brush to lightly touch the stylus (like you would be cleaning it) and see if it makes any noise in your speakers. Then do the same with the platter mat and record off and see it still makes noise when brushed. 

 

@mitchellcp 

Just for grins-even though you don't want to undertake onerous steps-please try switching the neutral and ground wires at the clips. Should take you less than a minute. I am sure you know this-use your fingernails and not pliers. 

The platter is solid aluminum.  Even if it had a layer of another metal hidden below, it would be a solid circumferential piece. It makes no sense to invent possibilities that are very remote and then feel satisfied that you know what is going on.  And even more important, if you watch the video, the pumping ceases when the LP and platter mat are removed!!!  If the platter per se was the cause, that would not happen.

I’m betting on static. I live in Utah and the air is incredibly dry.

Plastics can hold and build a charge see the OSHA Warning https://www.osha.gov/publications/hib19880930

I appreciate the response but if you watched the video............

One or several  points on the platter that are magnetic, not the whole platter.  The effect would be a similar to a Hall effect sensor.  Your MC cartridge is acting as the pickup.  Yes, the platter needs to rotate to make it work.  I’d venture a guess that you would see the woofers pulsing just by turning the platter slowly by hand.

   Could be something is oscillating in balanced mode but why would it go away when you removed LP and mat? Neither of which can “store energy” for more than milliseconds. And it would be kinetic energy, not electrical.

Maybe I can pick up some cheap XLR to RCA adapters just for fun and see if it repeats.

I think the problem is stored energy in the vinyl and the mat- either separately or combined. 
 

I’m not sure if an earth grounded chassis would help. This TT is not earth grounded. The motor power is a 2 prong feed from a 120/100 volt step down transformer. The native power being Japanese 100v 60hz.

 

I think it’s a red herring, meaning something else is or was going on that neither we nor the OP have detected. Which is why I asked the OP to see if he can recreate the phenomenon by restoring the original conditions. It cannot be the platter per se because we see the pumping disappears when LP and mat are removed. Funk Firm mat contains no metal either. I’d bet the pumping has either directly to do with balanced mode or has nothing to do with what we see.

I certainly don’t blame the OP for not wanting to change back to XLRs just for my/our benefit.

If it was a magnet on the platter, the problem would occur when the platter had no record or mat. If you look at the video, you’ll see that does not occur.

As others have said, it could also be a magnet on the platter used to read and calibrate speed.

@mijostyn static can build up on one section of the vinyl. As the record spins the area with static affects the magnets in the cartridge and causes the base to move in rhythm with the section moving underneath the cartridge.

I would be inclined to take a small magnet and run it over the platter to see if there is some point of attraction within the platter itself.  Simple test to do.  Very odd problem indeed.

@lewm , there may be a magnet in the control loop under the platter. Very common approach. One thing is for certain. It is either something on the platter or the oscillating motor. The oscillations are perfectly rhythmic at 33.3/minute. I seriously doubt the mat. Who puts magnetic material in record mats? If its the motor that would validate my feelings about DD motors.

@dadawada , No it is not static electricity. Static electricity would not produce a perfectly rhythmic motion. Static can also not cause induction because there is no current flow to create a magnetic field. Any path to ground would short it out.   

The Funk Firm mat is a plastic material.

The video already answers most of the questions and discards most of the solutions being discussed, please take a look before making a suggestion:

 

Static charge is the best explanation yet. I use an AQ Anti Static brush but it didn't do much if anything.

The OP clearly stated and also shows in the video that he’s using a Yamaha GT2000L, a very fine vintagE DD  TT with a coreless motor. So far as I can determine that platter is all aluminum. Which is why I asked about the platter mat, wondering whether it might be ferrous. I know nothing about the Funk Firm, but I’m guessing it contains no iron or copper.

It's the static electricity on the vinyl.

What kind of table & arm?  With that nice cartridge, I’m guessing it’s probably a pretty good quality one but it seems to me that if this only occurs when the platter is spinning, it’s a mechanical / vibrational issue in the plinth / tonearm connection, /suspension components or maybe the bearing.  A relatively cheap stethoscope you can get from CVS can help to locate the culprit. 

As you look at the video you pick up that the oscillations are rhythmic and that rhythm occurs at 33.3 times per minute. I think @ Lewm hit on it. There is either Iron in the platter or a sensor magnet that is inducing a voltage in the cartridge. That oscillation will cause distortion in the woofer. The solution is a less sensitive cartridge or a different turntable.  

I also have a Hana ML cartridge and I do have woofer pumping but only when the needle is in the groove. Do you have that issue as well?  I eventually installed a KAB subsonic filter and all is good. Just wondering if you found some other way to address that.