Tracking error distortion audibility


I recently unpacked my turntable from a couple of years of storage. It still sounds very good. Several times during playback of the first few albums I literally jumped from my chair to see which track was playing as it sounded so great. After a while I realized the "great" sound was always at one of the "null" points. They seem to occur at the approximately the proper place (about 125mm from spindle) and near the lead out groove. Questions:
Is this common? I have improved the resolution of my system since the table's been in storage but I don't remember hearing this before.
All others geometric sources of alignment error not defined by the null points (VTA, azimuth etc.) are essentially constant through out the arc correct? If so they should cancel out. I assume the remedy is a linear tracking arm but I am surprised at how obviously better the sound is at these two points.
Table - AR ES-1, Arm - Sumiko MMT, Cart. - Benz Glider, Pre - Audible Illusions, Speakers - Innersound electrostatic hybrid
Do linear arms really sound as good across the whole record as I hear at only the nulls with my set-up?
feathed
Hi Pryso,

The forward position of the stylus relative to the cartridge mounting holes is more of a statistical norm than an industry standard. Frank Schroeder has observed this norm to center around 9.25mm.

I know the ZYX (Airy-3 and Universe) come in at 9.00mm, and the Dynavectors vary, but in general fall into the 8.00 to 8.25mm region. I haven't compiled as large a database as Frank has, but don't doubt his 9.25 number.

SME's assumption is that you can compensate for these small differences in effective length by moving the arm for and aft in the track, to arrive at a workable combination of effective length (as dictated by your cartridge) and overhang/pivot-spindle.

In my early days at Galibier, I advocated this as well, using the articulated armboard to adjust pivot to spindle distance. To a certain extent, I trivialized the importance of offset angle as does SME.

While I now advocate the use of an arc protractor (certainly for precision in setting of effective length and overhang/pivot to spindle parameters), the importance of offset angle is still one that I would like to explore further.

In a conversation with Yip at MintLP, I posited that offset angle might be considerably less important than dialing in the effective length/overhang parameters (tracing the arc perfectly). Yip has been thinking the same thing.

Both of us however have been respecting all three parameters, and need to experiment with the effect of screwing this third one up (offset angle). Of course, with an arc protractor, it would be a simple matter of separating offset angle from the other two variables (e.g. tracing the arc) in order to observe the effects.

I'm thinking out loud here, but as I visualize the solution, a clockwise rotation of the cartridge (relative to that dictated by Baerwaald for example) would have the effect of shifting both your null points toward the record spindle. So, with a Baerwaald arc, you'd have an alignment that slightly favored the inner grooves as does Loefgren.

I need to both think this through as well as play with this a bit.

This concept of optimizing for the inner grooves at the expense of overall higher distortion in the majority of the record is an odd one to my way of thinking, yet I understand why the fellow who listens to large, romantic works with big climaxes might make this choice.

Back to our old friend, the SME ... Of course, there are two reasons for having a bit of play in the holes in the headshell holes - both of them relating to adjusting the offset angle: (a) due to an alternate effective length dictated by the fore/aft position of the stylus relative to the cartridge holes, and (b) to correct for "out of true" cantilevers resulting from normal production variances.

It's been too long since I owned an SME (an original Model V), but I don't recall much play in the cartridge holes in the headshell. I recall one poster commenting on this forum that he opened up the diameter if his holes a bit in order to play with offset angle.

Cheers,
Thom @ Galibier
Dear Pryso: +++++ " This is the first time I can recall anyone suggesting that overhang is arbitrary and can be set anyplace (i.e. at the end of the arm) at the user's discretion. " +++++

me either and the problem was/is that he never answer the " right " Dan question about the spindle to pivot distance. He say works with the DB protractor where you can't to measure any of those distances: effective length or spindle/pivot.

So everyone has to assume ( like you ) that the overhang and effective length were take it at " random " because there is no reference point taked about.

I think that maybe he has a misunderstood on the subject or needs an up-date but of course he can " drive " the road he choose it ( like it to us or not ) where he already has such " distortions " where only can have " great " sound around the lead out groove ( null pont ) due to its " odd " tonearm/cartridge set-up.

I'm with you, Halcro, Dan and Thom on the Feathed " argument ".

I always say that all of us ( in this forum ) have the opportunity to learn every single day from everyone: things are that we want it, a not always " easy " attitude.

Regards and enjoy the music.
Raul.
Hi Thom:

Of course I realize the headshell slots allow for offset adjustments as well as overhang. To simplify the argument (which seems to have become complex enough on its own!), I was focusing only on the overhang as it relates to individual cartridge dimensions. This was to address Feathed's quote regarding the headshell slots. And having met Brooks Berdan I will look forward to your report back with his take on this discussion.

I've never used an SME arm but it is fairly obvious that their mounting slot accommodates overhang adjustments. I hadn't considered their use of headshell holes rather than slots as limiting offset adjustments -- good point.

But as Raul points out, these forums are an opportunity to learn. So whenever anyone posts information that runs contrary to science or common knowledge there is also the chance to misinform. That is unless they can produce new proofs to support their position.
Hi all,
I'm getting a bit late into the fray of it all. I have the SAME inner groove distortion issue, AND every recipe that's been kicked around was tried, and failed.
Set-up is bit easier in my case I guess, since I sport an almost brand new SME-V arm, Peer Windfeld cart that's well played-in ~ 1/2 year on an SME-10 tt, ML326S phono-boards with SUT! Pass 350.5, Burmester 961 Mk3. So, call it high resolution is why I go into it.

I can move over-hang on the fly, VTA pretty much so, Azimuth is fixed on the V, and it IS ok (checked by mirror method), VTF has been tried as has been, also on the fly anti-skate. -------- AND I still have inner groove distortion. Marvellous reproduction every where else but through the last ~ 25% on the inside. I do understand the respondent arguing if he like me has tried all of that USUALLY brought up set-up stuff. Tried it all, nothing works!

Einstein once said: To keep on doing the same thing over and over, and expect different results -- IS THE SIGN OF INSANITY!

So, In also recall very well that the analogue fundi of Image-HiFi Mag. Dirk Sommer has been moaning about those "dreaded inner groove distortions" again!
Hallo, there is a guy on the level with M. Fremmer saying this?! How so?

Now my good Audio friend tried to fix his inner groove distortion --- and got it fixed beautily! Now he has OUTER GROOVE DISTORTION! Whow, not my idea of a fix either.

Why do I mention this? HE CAN'T SEEM TO HEAR IT!?!
So I think, it also has to do with hearing, like e.g. sibilants, and of course the higher you system resolution the more you CAN (or aught to) hear it.

Lastly I have a notion (but can not prove it) that it is EXACTLY this issue that make folks go for 10.5" - 12" tonearms.
(I'm sure we do not need to explain the geometry differences here)

Greetings...
Axelwahl,

What you are describing is NOT normal and does NOT have to be accepted. New or used arm doesn't matter. If one can't set up a 9" arm correctly, one probably can't set up a 12" arm correctly either.