INNER GROOVE DISTORTION

I would contact SS. Since Peter makes the cart, and knows a thing or two about VPI, he would be the only person I would listen to.

Thanks TJ.

Although I've read much regarding inner groove distortion.,,,, I, myself have never once experienced it. I've been in this hobby for 3+ decades So, I assume your set-up is incorrect..

I'll find out for sure, thanks for the response.

Joey, please get the version with the gimbal bearings! More than likely your problem is lack of anti skating. It could also be poor set up, turntable not level, etc. What you are doing is guessing. Guessing is not the way to set up a turntable. To adjust anti skating correctly you need a test record. It will allow you to find the best compromise. I like the Hi Fi News Test Record. You have some great equipment. It would be silly to compromise the lot with poor set up. Just a few minutes with the test record will demonstrate to you why you need an anti skate devise. You will never go without one again. You will get better bass with the gimbal bearings.

Mike

Sounds like you need to set up the anti skate. Check out Peters Tutorial on you tube. He absolutely believes that you need to use it. It made a huge difference on my VPI especially with the original 3 D Tonearm. You will most likely need some small washers in addition to the o rings to achieve the correct anti skate. The Tonearm should move very slowly towards the spindle while not in the record groove. Give it a shot u got nothing to lose.

Good suggestions above. I would also recheck your cartridge overhang & alignment. If that is good, Change VTA slightly... move the base of the arm up .050 (or so) & see if it changes anything. 

"Just twisting the cable ..." A Mickey Mouse attempt at anti-skate! This will not do! Replace that VPI arm with one with proper gimbal bearings and an anti-skate mechanism. Jelco arms are excellent and affordable!

Tilting the arm or table is also bad and stupid!

The idea that you MUST change your current arm or anti-skate adjustment to get rid of inner groove distortion is just ridiculous.  I and thousands of others with VPI unipivot arms have been doing just fine with them for a generation or more.

I use an old Shure test record that has a test for antiskating, the best available IMO. The Shure test records can be found at used record stores for a few dollars. My VPI arm with a "twist" passes the test perfectly.

There is obviously something very wrong with your setup that cannot be diagnosed at a distance.

Forty years ago at WSU my stereo skills were known so far and wide I had strangers calling me up for advice. Usually a few questions and boom problem solved. One time though I was thirsty, I can fix it, for a beer. When I already knew the fix. And so, walk in, where's my beer? Thanks! Quaff. Flick. Wow sounds great you're amazing here's another beer! (The half-life of a beer at WSU back then was in the milliseconds.)

So of course these things can be diagnosed and fixed at a distance. Its the beer delivery where things get a bit tricky.

But as for the "problem" the L channel information is on the left, R is right. I'm talking the groove as seen facing the turntable. So if the L is breaking up its bouncing off the inner side from too much anti-skating, so dial it back. If the R is breaking up its the other way around. And if BOTH are distorting then its nothing to do with skating, anti or otherwise, its the cartridge body is rotated too much one way or the other on the vertical axis, otherwise known as zenith. In that case go back to your Baerwald and fix the alignment problem.

Now, please PM me for delivery instructions. And make it a porter.

Oh wait, what’s this?

I don’t use anti-skating, just twisting the cable going to the junction box.

Actually knew that was there but only just now decided to use it. Classic example of why however good VPI are I’d never recommend one for the arm. Twisted wires. Sheesh!

So what happens is as the arm swings closer to the center the torque on the wire increases and this means a VPI arm will always have more anti-skate at the inside than at the outside. Its never right and anti-skate usually isn’t all that particular anyway (watch Lederman, explains beautifully why it is at best an average or trade-off) but still, twisted wires, I mean come on!

So odds are your twisted wires are twisted okay for the outside but too much for the inside. If this is the case then it will be the inside or Left channel that’s distorting the most.

Leavenworth Bulls Tooth. The porter, I mean.

It appears that the compliance of your cartridge is either 22 or 28 um/nM, depending on which version of The Voice it is. Either way, those numbers are high enough that if anti-skating is significantly misadjusted you should be able to see visible deflection of the cantilever to one side or the other when viewing the cartridge head-on while it is in the groove of a rotating record, relative to its position (nominally straight ahead) when the stylus is lifted off of the record.

I suggest that you take a look at that when the stylus is near the beginning, the middle, and the end of a rotating record, preferably during musical passages having relatively low volume. Too little anti-skating force will result in cantilever deflection to the right (toward the outside of the record); too much anti-skating force will result in deflection to the left (toward the center of the record).

Hopefully you will then be able to find an amount of twist that results in minimal or no deflection at all positions on the record.

Regards,
-- Al

I have toyed with twisting the tone arm wire, in my opinion it messes with azimuth which changes as it moves across the record. Much better to have nice even loop in the wire.

I'm with millercarbon.  If the distortion is "global" (i.e., in both channels), then I doubt it's due to a lack of anti-skate per se.  Also, if you had a pronounced lack or excess of anti-skating force, you would hear the effect at the outer grooves as well as at the inner grooves. As millercarbon mentioned, too little anti-skate affects the R channel predominantly, and you would hear R channel distortion from the first second the needle hits the LP.  Too much anti-skate will do the same in the L channel.  My guess is that the movement of the tonearm is impeded by something (wiring, maybe?), as the tonearm travels toward the spindle.  That said, I do agree with others that the lack of any provision for anti-skate typical of older VPI tonearms is egregious. Check also to see whether the cue-ing device is fouling the arm wand, as the arm pivots toward the spindle.  Likewise for the counter-wt.

Yeah, I'm a Neanderthal but my inner groove distortion bugaboos magically disappeared when I started avoiding spherical & elliptical styluses in favor of the more sophisticated profiles. Even though my line contact(?) Lyra Delos stylus is seeing its age, it'll track anything.  Even my hottest 45 rpm singles.

I use a 12" unipivot arm with no anti-skate adjustment, and I have zero audible inner groove distortion.

I am using a vintage NOS Fidelity Research MC with a line contact stylus.

Do not use the wire twist method...unreliable at best. I’m just wondering if antiscate is theoretical. I hear no difference with/without. I use a very minimum....just in case. I hear no inner groove issue ...although the beginning of the record always sounds better than the end

Wow! So many responses, much obliged friends. I am not going with the fatboy because of my problem! I did watch Peter Lederman and experimented with adding some anti-skating with some good results. When the tech from Overture Audio { who have been great } comes to swap out arms I won't let him leave until I am completely satisfied. I have too large an investment in this not to have great sound from the entire record. It's better but not like it should be. Really grateful to have access to so much knowledge Agoners.

I’ve never experienced IGD in any of my tables, with any of my cartridges. Not ever. Not in 50 years.  Whether conical, elliptical, hyper elliptical, LC, or Ridge Contact styli, I’ve never had it. Yes, other kinds of distortion from various problems, but never IGD. 

Currently i have 10 tables and 79 cartridges. But I always carefully align the carts in all axes, and I have always checked the performance of the antiskate when adjusting and checking out the table. I use a Lofgren B, DIN alignment. 

I will say that nearly everyone I've known that had IGD issues, failed to carefully and thoroughly check their table and cart. Nearly all could not answer questions about alignment.

I'm intrigued by the idea that the gimbaled fatboy is preferable to the uni-pivot. I await any experience/input. I listen mostly to classical and jazz but rock also. { Chick Corea says you can't label jazz as such anymore, but you know what I mean} As always, I appreciate the wisdom. Joe

For what it's worth, the bearing type would have nothing to do with the magnitude of the skating force, all other things being equal, or of the amount of anti-skate needed to correct distortion due to the skating force.  It's merely that with a unipivot, excessive skating force would tend to pull the azimuth off.  Whereas, with a gimbal type, the headshell cannot roll around its longitudinal axis, thus there can be no effect on azimuth.
And finally, I still say that excessive skating force or excessive anti-skate would cause distortion most noticeable in one of two channels, not both at the same time, and would not exclusively affect inner grooves.  Such errors should be noticeable all across the LP surface, to varying degrees depending upon the magnitude of the skating force at any point.

Hi Joe

I did watch Peter Lederman and experimented with adding some anti-skating with some good results.

So did you try lowering the stylus in between the runout grooves. What happened?

When the tech from Overture Audio { who have been great } comes to swap out arms I won’t let him leave until I am completely satisfied. I have too large an investment in this not to have great sound from the entire record.

He is going to put on a few records .Can’t do more than that. Your hearing while he is there - will not be in the same state as when you are alone, with friends, family, relaxed and listening. Just saying I used to do this for friends.

You can give a man a fish....or you can teach him to fish. In millercarbon’s case it seems a beer will do it. 8^0

*******************************

when someone posts as they have on your thread.

I hear no inner groove issue ...although the beginning of the record always sounds better than the end

That is describing inner groove distortion. No one on your thread seems to want to discuss the Elephant in the room. The Record.

There is a lot more vinyl, bigger grooves, at the beginning of a record. The grooves are much smaller at the end. The beginning of the record should be, based on physics, always sounding better at the beginning. How resolving ones room is (and their hearing) will factor into if one can hear this.

Due to the above - , "anything" that is going to impede the stylus travel, be it tonearm setup, alignment, antiskate, condition of record - will be heard more readily at the end. Another challenge for the vinyl audiophiles.

The above - the Inner Record Grooves - is Analog’s answer to - Digital Compression.

**********************************

Because my pivot arm’s cartridge is angled in (cocked in, as Peter from Soundsmith likes to say) - toward the spindle. The more friction in the groove (increased VTF) results in needing more anti skate. For this reason Peter’s test involving the Inner Groove test only goes so far.

Classical music - due to the varying levels of modulation (loudness) - is the biggest challenge against groove distortion and applying anti skate. We all are just trying to bring the distortion level down to a level that is bearable for us. And this "level" differs for all of us. JMO

Happy Listening and Merry Christmas to everyone.

The VPI  Gimbal pivot is better in some ways than is the single pivot (spike).  The more solid bass, etc. ...greater clarity from the gimbal can be had by adding the 2nd pivot modification to the spiked arm.  Easy to do and for 150 dollars is money well spent.

Ct, You wrote, ""anything" that is going to impede the stylus travel, be it tonearm setup, alignment, antiskate, condition of record - will be heard more readily at the end. Another challenge for the vinyl audiophiles."
Can you be more clear about what you wanted to say here? Because in some sense, none of the factors you list, maybe apart from dirt in the grooves, would be expected to impede stylus travel.  I believe the traditional meaning of the term "Inner Groove Distortion" refers to the fact that, as you mention, the LP has to crowd musical information into an increasingly shorter linear path, as the LP runs out of grooves. (Plus there is usually more tracking angle error on the innermost grooves, unless you're using Stevenson alignment.) There are analogies to this phenomenon in tape and digital reproduction as well.  Tape running at 15 ips and using half a track would be expected to provide much higher fidelity than the same tape running at 7.5 ips an using only one-quarter of a track, etc. And this is also why in theory 45 rpm sounds better than 33 rpm.  I'm sure you know this, which is why I wonder what you are saying above.

I must confess to have been very proud when I succeeded to
get 90 microns ''pure'' (without any buzz) with my (then) Ortofon
MC 20 with the help of my test record. The part about ''tracking
ability'' test. But then I come across the warning by Van den Hul:
''no antiskate is better than too much antiskate''. To get those
''impressieve'' 90 microns I needed to increase antiskate force.
So whenever ''buzz'' appeared in the right channel I increased the
anti skate. But thanks to Van den Hul I still have no idea how
much anti-skate is ''allowed''. So I use 0,5 g force for each cart. 

Almarg
Hopefully you will then be able to find an amount of twist that results in minimal or no deflection at all positions on the record.

@almarg

Hi Al - there are not multiple twisting increments permitted with the design. It’s more like .....are you going to do One twist or nothing.
To explain. If you look at the wire loop in the attached pic link. my former VPI JMW 12 tonearm.

https://photos.app.goo.gl/M2KjNpVbyxNCbbHM6

imo - Unless VPI has changed the materials used (wire and teflon coating type) in later wire loops.... then there is not a lot of twisting that can be done here. The wire loop is of a "construction" that provides for push back when "not" twisted. So anti-skate is there without any twisting. In addition to this, the springing action of the wiring provides for increased anti skate action as the loop is "closed" towards the end of the record.

I assume, when VPI added in an anti skate mechanism in later years, the amount of AS needed, would be below minimal, due to the anti skate action of the wiring itself.

From what I recall adding in even one twist of the wire for me - produced problems as other posters on this thread indicated. I also wonder how many of those taking shots at this tonearm / wiring technique - ever owned a VPI uni pivot tonearm ?

Cheers Chris

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.