INNER GROOVE DISTORTION


Seasons greetings! I have a VPI Prime Sig. with a Soundsmith " The Voice " cart. and am having an issue with inner groove distortion. I don't use anti-skating, just twisting the cable going to the junction box. I will be upgrading the arm to a Fatboy soon and when the tech comes to set it up we will address the issue. On some records I can't listen to the last song! Frustrating, any feedback will be appreciated. Also, have Pass XP-25, ARC Ref 3 and 75 with ML ESL11A's. Thanks.
joeyfed55
Joey's problem is probably due to several factors conspiring against inner groove tracking.
It does appear people tend to underestimate the skating force. If you think you are going to counter it with twisted 24 gauge wire at the fulcrum of a 9 to 12 inch lever arm you might as well try to stop a car rolling down hill by standing in front of it. Defeat your anti skating device and try playing a blank side. I would suggest putting an old worn out cartridge in first. Play a record and gently defeat your anti skating device by lifting it up and watch carefully to what happens to the cantilever. It will deviate a millimeter or two to the outside as the stylus leans heavily on the left channel unloading the right channel. Play a Hi Fi News anti skating set up groove and listen to what happens to the distortion in the right channel when you defeat the anti skating device. I might further add that in regards to vinyl playback distortion = record wear. 
Simonmoon, I highly recommend getting the new 3D printed 12" gimbal tonearm with anti skating by VPI. I do think this would make more than a trivial improvement in your vinyl playback given your current situation.

Mike
lewm - Because in some sense, none of the factors you list, maybe apart from dirt in the grooves, would be expected to impede stylus travel.


@lewm

"some sense" ??

ok here we go - hang on ....

In "some sense", when a record is cut, one spiraling, varying, groove gets created.

In "some sense" the best vinyl re-play design we can re-create, is to duplicate the record cutting process, but in play mode ,with a stylus that resembles the cutting stylus.

In "some sense" - we cannot eliminate the friction created by the play stylus against the groove walls as this is needed to start production of the signal. We do know that laser vinyl playing never took off.

So "some sense" therefore says...

Anything, and all things, that affect the travel through this groove in a way different from the way it was cut...... that creates more friction.... than the friction the stylus produces, if it was travelling the groove AS CUT........ will impede stylus travel.

In "some sense" this includes an improperly setup and or bad design linear tracker tonearm.

In "some sense" this includes the extra friction caused by a pivot tonearm’s behavior to push inside due to the cocked cartridge position.

Hey
I have talked to Peter at Soundsmith about uneven wear on carts that get sent to him for repair. This is real. Now imagine test driving a brand new car down a very narrow road, and the car had one bad design feature..... it constantly pulls to the right. 8^0

In "some sense" this includes the use of anti skate to fight off this inward tendency thus producing a constant tug of war. This impedes stylus travel.

Empirical observation based on ^^^^.

If you had ever heard a properly set up air bearing linear tracker play the inner grooves cleanly in your own space, then you would of heard this Pivot tonearm "tug of war".

In "some sense" there are times in this audio hobby, when it is not until you "remove" a problem to understand, it was there to begin with.

In "some sense " the record sounds better at the beginning than the end" (famous saying by any owner of a Pivot arm which includes me)

"some sense."

Has anyone remarked that is experiencing inner groove distortion, if at at the end of a record....does the arm move steadily toward the end of it's travel and stay there?
Ct, My question was a simple one, I thought.  You named the following as factors that impede the stylus: "tonearm setup, alignment [which is really the same thing], antiskate, condition of record".  A lot of this depends upon how you look at it, but I would say that tonearm setup/alignment, and antiskate do not impede the stylus, unless any of those factors was impossibly cockeyed. Of course, as you say, friction between stylus and groove is the major impediment and the root cause of the skating force, and probably groove tortuosity due to complexity of the encoded musical signal adds to the effect of friction. Plus dirt.
My earlier question may seem simplistic but, really this is simplistic. If your tonearm moves steady toward the label and doesn't, at all want to bounce back, your anti-skate set-up is very good. Cross that off your list.