Question about Inner Groove Distortion (especially on shorter records)

I was playing some Aerosmith records, particularly Rocks (original American pressing), and I noticed the last couple of tracks sounded pretty bad with inner groove distortion. What's baffling to me is that it's such a relatively short album at around 35-ish mins. I've had plenty of albums where they are not only of the same length but pushing well past 40 mins where IGD isn't nearly as bad.

The cartridge I have is a Grado Black with a U-Turn Orbit and Pluto Pre-Amp. At its best, IGD is very admirably mitigated but almost always present in some form with the Grado, but definitely listenable on the "better" records.

My question is, why is it so bad on this album (and most early Aerosmith albums) that are all about 35 minutes in length? I've also seen it be almost as bad with some Blue Oyster Cult albums, particularly Agents of Fortune which also runs about the same, and both bands were with Columbia Records.

My other question is (a few, really), are the inner grooves of those albums, as they say "worn out"? Like, if played on a higher-grade cart with really good tracking, would it not make a difference, and I may as well look for another copy?

In other words let's put it this way: let's say there's two identical albums, same inner groove/deadwax info and everything. One of them is the copy of Rocks that I have, with the issues I described above, and another is a barely-played copy of that same album elsewhere. Is there a discrepancy in how much IGD in both where mine was probably played on a badly aligned table or played quite a lot, or are they all like this and playing the albums on a higher end cart yield identical results (hopefully cleaner sound)?

That was a mouthful, hopefully I didn't confuse anyone. Thanks!

 

Pardon me if this is blatantly obvious, but IGD is generally the result of cartridge misalignment. Have you checked recently with a protractor? Also you might want to check VTF and anti-skating settings. Odd, though, that the problem is only with the shorter LPs. Other members may know more about this and weigh in.

 

It's not only with shorter LPs. I was asking as to why it's happening with these shorter LPs. Of course, I do have some longer ones with that same thing as well.

But mine came pre-aligned from the company itself. I've always heard that unless you get a $150+ cart with a certain kind of stylus, you'll get IGD of some kind; It's part of life when it comes to vinyl. My last TT, an AT-LP60 had barely any settings and the most basic proprietary cart so I got even harsher IGD.

 

I have an orbit with an Ortofon 2M Red...I would definitely check the cartridge alignment and VTF regardless. You can't adjust the anti-skating on that turntable, so one less thing to check. Most records I play have little to no IGD, but a few it is very noticeable and they seem otherwise okay. I do recall from previous turntables with Grado cartridges that they can be tricky to dial in- I was unable to ever completely eliminate IGD.

 

I had a Grado cart once, It didn't last long due to IGD.

 

Sometimes when cutting an LP short that is short time-wise, the engineer will reduce the groove pitch (spread the grooves further apart) to fill up the side and make it look "normal".

The important thing is not the running time of the side, but the diameter of the inner-most grooves where you hear the problem. If the distortion problem is happening close to the minimum inner diameter of the LP it might only be normal inner groove distortion. If it's happening at more typical inner-middle diameters, then maybe something's going on with your turntable or cartridge setup.

"...let's say there's two identical albums, same inner groove/deadwax info and everything. One of them is the copy of Rocks that I have, with the issues I described above, and another is a barely-played copy of that same album elsewhere. Is there a discrepancy in how much IGD in both where mine was probably played on a badly aligned table or played quite a lot, or are they all like this and playing the albums on a higher end cart yield identical results (hopefully cleaner sound)?"

That's a great question. I'm not certain of the answer, but I suspect that a turntable that's set up incorrectly will cause more damage to inner grooves than a properly set up turntable.

 

This.

Groove wear at the inner grooves is definitely a thing with used vinyl. Even if the table of the previous owner was set up correctly, there are many records that no bog standard elliptical or conical will track right, period. What happens is the stylus rides up on one side of the groove or struggles to stay centered in the groove. This carves a unique pattern that can result in baked-in distortion that will never go away.

Even if you get rid of the Grado Black and buy a cartridge with a very good advanced stylus, you may still get distortion on that particular LP.

All this is why I stick mainly with advanced styli now. I have a conical cartridge for beater records, but no more ellipticals for me.

 

Here is a pic of some of the narrowest inner grooves I've seen. The record is a six track EP by a French Techno producer. Only a few mm of deadwax on the b-side.

 

With a pivoted arm it's going to depend on which alignment you choose to use. Is the cartridge more perpendicular to the grooves at the outside or the spindle side? The longer the arm the shallower the arc also. The closer you get to the spindle the closer together everything gets and you end up with the"pinch effect" which can only be counteracted with a smaller stylus, longer arm or linear tracking or a 45rpm version of a 33rpm cut or possibly a different cut with less high frequency levels.

 

Could be an alignment issue. My suspicion is it’s an incompatibility issue between the Grado and the Orbit. I have heard a Grado Black sound exactly as you describe on one of my older tables (Rega Planar2 or SL1200) that sounded absolutely perfect with zero mistracking or IGD when aligned on a Pioneer PL530.
More recently I have been helping a record shop owner by doing setups on older tables he’s taken in from customers who unloaded their record collections. He usually hooks me up with a stack of used LPs so we’re both happy. Anyhow he had an older JVC or Technics DD, a truly low end table even for its time. The original Grado long body cartridge was still on and there wasn’t much setup to do other than to clean the awful buildup from the stylus. That done he played several albums in the store to test and even without much setting up or alignment that table played great and tracked smoothly.

So my experience is sometimes it’s a matter of finding the cartridge a turntable likes and sticking with it.

 

The so-called "inner groove distortion" is the "TRACING DISTORTION" proper fundamentally to the mechanical reproduction of ANY groove (and not only "inner") of gramophone record, and by ANY stylus, due to the difference between the shapes of the cutter chisel and the stylus. But to a variable degree depending, at equal frequency, on the radius of the groove. And in the same groove, on the shape of the stylus' surface in contact with the groove.

The tracing distortion exists on ANY groove, not at “inner” ones. Because the stylus is incapable of tracing ANY groove exactly as the cutting chisel does. But it increases from the outer to the inner grooves.

Example of explanation:
“By 1963, it was well-known that the 0.7-mil stylus which was used to play LP’s, would cause a significant amount of distortion as the ball-shaped tip attempted to trace the path cut by the chisel-shaped cutter stylus. This is called tracing distortion. You cannot use a chisel-shaped stylus to play records, because it would put too much stress on the plastic and damage the grooves.”
Article: Dynagroove: The Sound of Tomorrow
===

The only way to reduce it very considerably with "mechanical" cartridges: the use of styli designed and manufactured for CD-4 DISCRETE quadraphonic reproduction, or their modern analogues:
Example : "Micro Ridge"
Micro Ridge Stylus | Dynavector International Site
and similar.

 

To my understanding, some degree of IGD is inevitable:

"LTED (lateral tracking-error distortion), it turns out, is inversely proportional to linear groove speed, and so the same LTE at the innermost modulated groove radius of an LP will result in about 2.5? higher distortion than the same angular error at the outermost modulated groove radius."
Arc Angles: Optimizing Tonearm Geometry Page 2

Unless you can somehow start with zero distortion in the outer grooves, it seems there will always be some amount of inner-groove distortion. Presumably, proper alignment can minimize the effects.
-Bob

 

So right now, this could be one of 4 things:

• Misalignment
• Worn Stylus
• Worn Records
• Poorly cut records

Its impossible to know what the problem is until we narrow it down a lot more. Testing newly pressed records will help excluding worn grooves although, once we can exclude worn stylus and misalignment that becomes a possibility for your older records. Misalignment should be checked for, dont trust any company to do it for you completely unless you know the person doing it and that they do it well.

 

So right now, ignoring the unremovable “TRACING distortion” (described above) while playing gramophone records, well, as you please!..

 

I didnt even get what you were trying to explain. Do you mean the geometrical problem of not having a stylus tangential to the grooves, especially closer to the label?

 

I think he refers to the pinch effect.

Pinch Effect Distortion Calculator- Vinyl Engine

 

Right. Well its also part of the geometrical problem. It wont be an issue on even close to all records however and it should start to become only a very slight issue with Ellipticals even. You dont need a 1000$ cart to remove most distortion from your playback.

 

I used to have many of the same problems as the OP. I also am familiar with US pressings of Aerosmith and BOC. I too had issues with some of those titles. I tried just about everything to get things right on my prior cartridge, which was a Shelter 501. It sounded really nice musically, but I could never get rid of the dreaded inner groove distortion, even out of new records sometimes. After reading so much praise for Audio Technica, I decided to get the AT33PTG/II cart. The distortions are virtually gone. The stylus plays through those grooves on my BOC records with the ease of a knife going through a soft stick of butter. I will never go back to an elliptical cart again. I'm pretty sure AT makes cheaper models than the one I have that trace just as well. I would consider something like that if all the settings and experimentation with geometry do not pan out for the OP.

 

I am not as convinced as you, other than you don't need an expensive cartridge. An AT95VL should be good enough.

 

Wait, convinced about what exactly? And yes, audible distortion shouldnt be on nearly every record even if its a conical. Only if its some poorly installed Crosley esc player is that the case as far as Im aware.

 

I'd echo the others who say that inner groover distortion is definitely not alway due to cartridge misalignment. I used to have terrible IGD on an awful lot of records. At one point, I even took my turntable to a very reputable local audio repair shop to make sure my cartridge (a Grado gold, at that time) was aligned correctly (it was) and that the stylus wasn't worn (it wasn't).

But then I started using the AT440MLa cartridge and IGD was gone in all but the most egregious cases, in which the problem was likely worn grooves or poorly cut records. (And even in those few cases where there was still some IGD, it was still better/more listenable than with previous cartridges.)

I don't want to downplay cartridge alignment (nor VTF, anti-skate, etc.) - it's absolutely crucial (and it can be a pain in the ass to get right) - but I had IGD with a variety of cartridges (some worse than others) before getting the 440MLa. That was over 12 years ago, and I haven't looked back.

 

Convinced that it is a only a slight issue with ellipticals. If the stylus is a true elliptical footprint it needs to be more than a conical with flat shave off areas in the back and front.

 

Yes, the goal is basically making the profile as thin as possible to make it fit in any type of groove. Elliptical wont remove all distortion like finer profiles, but a whole record isnt cut at 20KHZ either. There will be some sibilance and IGD on some records, but it also depends on the type of Elliptical. It can range from 7x4 to 7x2, one double the thickness of the other.
Its not very often I hear distracting distortion with my Nag200 for example.

 

I'd have to look, I think I have one close to that, but I think yours takes the cake!
How's it play?
I have quite a few 10 incher's, none exhibit any issues.

 

Yes, and therefore I am convinced that the problem that the OP describes may in part be due to the Grado Blacks elliptical stylus. I do also have inner groove distortion with e.g. OM10 but the problem is reduced and sometimes much less using the OM40 or Shure V15Vx/JICO SAS stylus. So besides having correct settings, you will benefit with a finer stylus.