Does "perfect alignment of cart" eliminate 100% ?


Does perfect alignment or close to perfect eliminate 100% inner groove distortion ?
I have alignmed my arm and table a lot of times only to still hear some IGD ? granting one can perfectly align the cart, can one eliminate it 100% on all LPs ? or does most of us here still get IGD ? only some are minimal ?
nolitan
I am with Audiofeil on this.

The Mintlp is a great tool. We used it when we set the table up. I had the alignment off, the table was not level, azimuth was off and the tracking angle was wrong. Basically, I had everything wrong. The funny thing is that I have been working on my table for a year and knew all of this but could not put it all together. I did not know what to listen for when setting the VTA or azimuth. My friend has better ears than me. The music dropped back about two feet behind the speakers when the VTA was locked in. I had it too low. When he leveled the table it made a huge difference. It was not off much but it made a big difference when spot on. He used the bubble level on the inner part of the platter near the spindle. I learned a lot from him in 30 minutes than I learned by myself in a year. It helps to know someone who knows what they are doing. I still do have some IGD, but he said that my tonearm/cartridge combo was as good as it would get. He also said a Lyra cartridge would probably track much better than the Benz H2 and that the scout although a decent table for the money is not the best. I need a better tonearm. He said that is half the battle and is key. A tonearm upgrade and cartridge that will work with the arm is what will ultimately improve the tracking. So I am saving my pennies.
>>06-15-10: Vinyladdict
Stylus profile, in my experience, has much more to do with the elimination of IGD than any other parameter.<<

Nope. Precise alignment is the key.

The stylus profile contributes to good tracking but all stylii will minimize IGD provided the cartridge/tonearm match is proper.
The question that must be asked ... what cartridge?

Stylus profile, in my experience, has much more to do with the elimination of IGD than any other parameter.
It is possible to have no inner groove distortion. A friend of mine has no inner groove ditortion on his old Mission Turntable. It sounded better than the VPI Aries I heard at the dealer. His table is over 20 years old. lol. He is a master at setup. He came over and set my table up. My table sounds unbelievable now. I have a scout. His table still sounds much better than mine. He is using a Lyra Dorian cartridge. I am using a Benz H2. He said that all of the High output moving coil cartridges will not be able to come close to the low output MC's. He said the MM cartridges will have less tracking error purely due to their design. However, the low output moving coils are where its at. Many things made a huge difference. For one, make sure your table is level, another is make sure the VTA is not too high or too low. Azimuth is critical. It is all important. He told me next cartridge I get should be a low output moving coil. The high out moving coils negate the purpose of having a moving coil cartridge so I am told There is too much mass due to the extra windings on the coils restricting the movement of the cantilever in the groove. This is most important on the inner grooves and during complicated musical passages, especially something like a cannon shot on the 1812 Overture. One thing I have come to realize is that I cannot expect miracles from old shaded dogs and Bluebacks and other old lp's. They are just too worn for the most part. Of course unless you are lucky enough to come across a mint copy. Most used records were played on very mediocre tables that were not set up properly, some had quarters on the headshell. However, will proper alignment and setup, these old records can suprisingly sound very good.
"It's called "un-distortion", a world where everything becomes crystal clear and transparent."

Oh! You mean like CDs, right? :-)
-Bob
It's called "un-distortion", a world where everything becomes crystal clear and transparent. They use it at airports.
An interesting passage from Keith Howard's "Arc Angles" article in the March "Stereophile:"

"In fact there is another vital parameter, namely linear groove speed (that is, the speed at which the groove passes the stylus), which varies by a factor of about 2.5 from the outermost to innermost modulated groove radius of an LP. LTED (lateral tracking-angle 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 2.5x higher distortion than the same angular error at the outermost modulated groove radius."

Does this mean that those who have zero inner-groove distortion also have less-than-zero distortion at the outer grooves?

-Bob
Some arms are more affected than others, yes. Mistracking in the inner grooves might also be caused by the mechanical resonance of the arm/cartridge being slightly too high.

Electrical loading of the cartridge can help too.

Some preamps will exhibit a distortion that sounds a lot like mistracking. This seems to show up in less expensive solid state units that use excessive feedback.
I did notice that playing with the alignment did help reduce the IGD but its not 100percent eliminated.
Does incorrect anti-skate setting also causes IGD ?
Dgad, that is an excellent point. Speed stability can also be the last piece to eliminating sibilance.
Nolitan,

Another cause of inner groove distortion can be your motor. I have had a friend upgrade his motor and noticed an eliminatoin on IGD due to the upgrade. Speed stability issues are more apparent on the inner grooves.
I have a Triplanar, a ZYX Universe and a Transfiguration Orpheus. Neither exhibits even a slight amount of mistracking at the inner grooves. One day one of my cartridges died, and while it was being fixed, I used a Grado Green, which retails for about $35.00 or so. No inner groove issues at all, in fact it seemed to track as well as the other two cartridges. It took a bit of experimentation to load the cartridge, and after that it was quite musical.

What you can take from this is that initial setup, the match of the weight and compliance of the cartridge, in tandem with the effective mass and mechanical resonance of the resulting playback apparatus, is **everything**. If the arm has midrange resonances in the arm tube you could still get into trouble, and there must by no, nada, zero play in the bearings of the pivot!!
I agree with Dan_ed and Onhwy61. I too can play 99% of my LPs with no IGD. Unless there's a great deal of wear on the disc, all is well. Of course, alignment is only absolutely correct at the two null points (given Loefgren or Baerwald) - every other place across the traced path of a pivoted tonearm has some degree of error. Ironically, the grossest tracking error occurs not at the end of the LP side, but at the beginning.

-Richard
How old is the cartridge and was it a used one? Might be worn out prematurely due to improper setup.
Nolitan,

yes, I can play my LP's with no inner groove distortion. I would wager that most everyone I know whose systems I have heard can also play with no inner groove distortion. If you are hearing this there is something not correct in your setup.
What cartridge are you using? My understanding is some carts are going to give a little more IGD than others, even if they excel in other areas.

I'm using an AT440MLa on a Technics 1200. Not the highest-fi setup, but the AT tracks well, and I don't hear any IGD.

And for the record, I set it up with the TT Basics mirror protractor(with a string taped to the sight line to help make sure it was pointed at the pivot).

Eric
In short, is it a majority of us experiencing IGD or some of you guys can claim that you can play most of your LPs w/out any IGD ?
You can download a Stevenson protractor at the link below. Actually, it combines Baerwald and Lofgren (presumably "B"), too. I've never had any problem printing the protractor at 1:1 onto an inexpensive photo paper. Works fine for me. The only possible caveat is that you have to line it up to the exact pivot point of your tonearm, which I understand is difficult with some arms. Go the the link below and click on the KWillis Universal Accutrak Protractor Version 2.
-Bob

http://www.vinylengine.com/cartridge-alignment-protractors.shtml
None of the currently popular protractors use Stevenson, as far as I know, because Stevenson is slightly out of favor compared to Baerwald and Lofgren A, in that order of preference. You might google it to see if there is something available. There is a rudimentary protractor available on Vinyl Engine for free, but you have to print it at 1:1 ratio and mount it in some rigid substrate in order to use it accurately. Stevenson gives an inner null point at about 60mm, which is at the innermost of any inner grooves. I recently saw some measurements of typical LPs, and in many cases the grooves had run out before the 60mm radius from the spindle as centerpoint, i.e., the true inner r was >60mm. This means that in some cases Stevenson will not give you two null points over the course of an LP, only the outer one. Having said all that, if you have a vintage Japanese tonearm, chances are it was optimized for Stevenson (In that the offset angle of the headshell is best for Stevenson alignment), and you might therefore want to use it. Finally, don't get overly obsessed with this issue; it ain't worth it.
Dear Nolitan: In a pivot tonearm you can't eliminate 100%. If you want minimum distortion at inner grooves then align your cartridge/tonearm with Stevenson geometry.
If after that you still heard that IGD then maybe the tonearm or the cartridge or both are out of specs or are not a good match between them.

Regards and enjoy the music,
Raul.
If you are using a pivoting arm, at best you might be close to "perfectly aligned" at only two points on the record. I would continue setting up the cartridge.
The March issue of Stereophile had an excellent, many page article entitled "LP Tracking Error Explained". There is no such thing as perfect alignment. It's all been pretty much guess work from the beginning. Just get as close as you can and listen to the music...that's what it's all about.
There's no such thing as perfect alignment. All alignment tools are approximations only, and their accuracy varies as the cartridge sweeps across the record. Furthermore, the thickness of the vinyl influences the geometry somewhat and varies from LP to LP, so unless you are prepared to set the alignment for each LP, you might as well leave well enough alone.

Cheers
If you're talking about it happening on many records, then your cartridge setup needs work. If it's only on one or two records, it could be the recordings or your specific discs.
Be realistic. If you can hear a problem try to sort it - if not, leave it alone and listen to music. If you can't hear a deterioration then you are OK as the stylus will be operating within its tolerances. If you do, then you can try altering the alignment - simple.