Mounting of a tonearm.

I have an Oracle turntable with a rare Micro Seiki TA-1 tonearm. I don't have any dimensions or instructions for the installation of the tonearm.
How critical is the measurement from the spindle to the tonearm.?
How would i be able to determine the correct measurement ?

The tonearm sounds great the way it is installed but on some recordings i hear a little distortion on the last track and i am wondering if this dimension would have anything to do with it.
IIRC, innermost tracks are hardest for the stylus to track. Try adding a touch more VTF or anti-skate.
Have tried up to max antiskate but makes no difference.
I have aligned cartridge the best i can and adjusted VTF no improvement.
I would like to find out how to determine the correct mounting position of the tonearm from the spindle.I think this could effect the tracking error. Or is the spindle to tonearm distance that critical?
I am not familiar with the Micro Seiki TA-1 arm but if it has a slotted headshell then the arm location is not critical. The distance that matters is from the stylus to the pivot point and this can be adjusted by moving the cartridge in the headshell.
2002ss335 is correct.


Arm mounting distance per se has little sonic effect. It's true every arm is designed for some specific mounting distance, but that distance was chosen for one reason only - to ennable a particular cartridge alignment geometry (Baerwald, Stevenson, Rega, single point, etc.) If a cartridge can be aligned using the intended geometry then the arm mounting distance is close enough. Moving the arm a mm or two will have little practical effect. You'll have to move the cartridge in the opposite direction to compensate and you'll be right back where you started.

Interestingly, if you're using (or wish to use) a non-specified alignment geometry you can choose a non-specified arm mounting distance. I have intentionally mounted tonearms at non-specified dimensions in order to use a better alignment geometry than the one intended by the arm manufacturer. Superior alignment geometry matters much more than tonearm mounting distance.


IGD is not caused by incorrect VTF, VTA or antiskating. Those mis-adjustments sound quite different.

While incorrect cartridge zenith alignment or an inferior geometry do contribute to IGD, in my experience it is mostly caused by inadequate cartridges. I have cartridges that produce audible IGD on any arm no matter how they're aligned. I have other cartridges which do not produce much audible IGD at all, even when misaligned.

Stylus profile seems to be the biggest factor. The finer the stylus contact surfaces, the less IGD. Spherical and elliptical styli are the worst. Line contact styli are better. Micro-ridge styli are better still. It is difficult to set a micro-ridge stylus up badly enough to produce audible IGD.

An inadequate phono stage can also substantially worsen the effects of IGD. This is a less explored area, but it's easily heard and demonstrated if you have multiple phono stages to perform comparisons.
You might have a worn stylus?
I use a koetsu blue onyx an sme 5. It has an eliptical stylus, all the top koetsus do as far as I can understand.
I dont have these probles but some older (70s or earlier can occaisonally show some IGD. The only ones I've come across are secondhand/well used records. The implication being haevy use with a large old old colaro maybe with really heavy sping-loaded arm and a rather crude stylus a.k.a. a SPIKE!
Best of luck
Thanks everyone for your feedback. I have found after very careful checking of adjustments that the distortion i am hearing is on the record i am playing. It only happens on the last track of one lp. When i first heard the distortion i thought it was in the setup so i tried re-adjusting everything i could but could not reduce it. I was concentrating on that one lp only cause the lp was only 3 weeks old with maybe 5 plays and thought it should not have any distortion it is new. I noticed the distortion from day one but thought it was setup issues. I played a dozen records or so last night and heard some distortion but only a couple times on some 35 year old records.
I am new to vinyl so i am not sure what distortion is part of the setup or on the lp.

I am using a ZYX airy 3 which should track just about anything . I have some cartridge alignment tools on the way , so far i am just using a paper template i downloaded off the internet from Enjoy the music.

Thanks again
That's good news.

IGD is a function of tracking angle error and the shorter modulations of inner grooves, but that's not your problem or you'd have it on many records. IGD has nothing to do with the age or condition of any particular record, so the term doesn't apply here.

Out of curiosity, which LP is this and what does the distortion sound like? It might be interestng to figure out what's actually happening.
Thanks Doug for providing a good insight to IGD. IMO, IGD is most likely caused by a worn stylus.

welcome to the whacky, insane world of vinyl! Sounds like you've discovered my number 1 rule of thumb. First assume the simplest (dumbest in my case) scenario and work your way up.
Sorry guys for not replying sooner , have been away.
I have 2 new Clear Audio records that do it. One is Friends of Carlotta on the track Time
After Time , at the very beginning the piano has some smearing type distortion. The second record is Bella- tracks of the heart. The electric guitar has the same type of distortion .Both of the instruments have large amounts of echo mixed in so it could be in the recording. The funny thing is the voices are crystal clear with no distortion ,it is only these 2 instruments on 2 tracks.
I don't know how to describe the distortion i am hearing i don't know the correct terminology for all the distortions.

I have been using Doug's cleaning method with the Magic eraser after every play and the stylus is very clean now. I am now using Audio Intelligent #6 cleaning solution and things are sounding great except for the distortion. I am beginning to suspect the tonearm but the interesting thing is it only distorts on specific tracks on certain records at different locations on the records too.
I have learned alot in the last month and the sound has improved an incredible amount thanks to Doug and everyone else that has helped out.

Thanks for the further description.

"Smearing" is an excellent description of what can result from tracking angle error distortion.

When the cantilever is non-tangent to the groove (as it is on an LP's inner- and outer-most grooves) the stylus contact edges play the two groove walls with a slight time shift. The only way to prevent this is to use a linear tracking arm. All pivoted arms produce tracking angle errors. The only way to reduce them is to fiddle with your cartridge alignment. Eliminating them will not be possible. Tracking angle errors are a mathematical certainty with a pivoting arm, one of the irreducible weaknesses of vinyl playback.

BTW, it's unsurprising that one of your problem passages is on the very first grooves. Tracking angle error is highest on the first grooves of an LP (assuming a two-point cartridge alignment).

Now if an LP were artificially mixed with 100% unique information on each channel (ping-pong stereo) this slight time shift wouldn't matter. But most LP's have information from any given instrument on both channels. That is what gives us imaging, lateral soundstaging and image placement. Certainly all live, acoustic recordings do this (most classical and jazz). With the same information on both channels, any time shift between channels puts sounds that should be congruent slightly out of phase.

Echoes and reverb add to the challenge, since they're another example of time-shifted sounds.

If a system maintains these slight phase shifts perfectly all the way through the speakers, it doesn't sound smeared. Images shift L or R from where they should be, but that's about the only effect. The trick is getting the system NOT to smear similar or identical but phase-shifted sounds into mush.

This depends on every component in the chain. Any time you put two similar waveforms with a slight time shift through a component you are testing its temporal linearity, transparency and ability to resolve and maintain very fine differences. My toughest test LP's for this phenomenon contain strong, pure tones from two very similar sources (alto recorder, alto vocalist) playing identical or harmonically related notes at the same time. The recording was made in a stone-walled church, so in addition to the doubled voices the echoes are quick, powerful and closely overlapping. This LP brings most systems to their knees. I've been working on ours for five years and it's "almost" right, but it's been a long struggle.

The phono stage probably has the toughest job, since it has to amplify the lowest level signals without mushing them together. I've only heard two or three phono stages that can cope with my toughest LP's in this respect. I've heard many more that blend similar waveforms into a distorted smear.

Line stages and amps can do the same thing of course. So can tonearms, interconnects, speaker cables and speakers. Every component in the signal path is an opportunity for phase shifting and distortion. The best components minimize this and that's a major part of what we've strived to achieve with our system.

One thing I can say from experience is that your Airy 3 is not a major contributor to the problem. It doesn't have the unearthly transparency of the UNIverse, but even entry level ZYX's like the Bloom present difficult signals to the phono stage with exceptional clarity. Maintaining that clarity is difficult however. In that respect a ZYX may challenge a system in ways that some less resolving cartridges simply gloss over.
Hi Dougdeacon,
great insight on (inner / outer) groove distortion in my opinion.
I have these issues with an SME V arm with currently Ortofon Windfeld.
VTA and VTF as well as Azimuth seems of rather small influence since it is VERY little variable with this set-up.
Windfeld is VERY low riding => resulting very small VTA change range (else rear of cart touching record), arm has dynamic VTF adjustment => balance stylus just over 180 gramm record, add Ortofon Windfeld spec 2.6g, according to SME scale (pretty correct I should think).
Azimuth also very little adjustment possible, since only via 3 point Windfeld mounting support +/- 1-2 deg.
All been checked over and over to be found REALLY fine.
My question:
What is your best take on source of distortion when this ONLY happens during "high energy" treble in the last halve of the band?
Example DECCA SXL 2248, La Boheme, Tebaldi/Berganzi Highlights. When Tebaldi 'blasts' at the end of side one, I had no pick-up as yet to really handle it too well. Carts I had this far: Ortofon Jubilee, Windfeld (current), Lyra Dorian, and DV 20X-L all known to be good trackers to my knowledge.

PS Audio GCPH, and currently Levinson ML326S phono-boards (both differential designs). Currently using Fidelity Research XF-1 type M, (1:31.6 = 30dB) with 13 ohm PRIMARY! to fully impedance match loading >=10ohm cart - 10.18 ohm at SUT primary. This sounding better than straight into phono-boards, which then had needed loading between 500 - 47k ohm (mostly sounding the same! with Windfeld)
Dear all, I strongly recommend for all interested in tonearm geometry and its proper application the highly controversial thread "Prices of oldskool tonearms" here on Audiogon Analog. It goes into the very detail of the topic and illustrates, why absolute precise tonearm alignment is so important.
"Prices of oldskool tonearms" very good,
Now what was the last entrie?
Or is the yet some search facility?
Forums - Analog - page 2,3 or 4 . Last entry was about march 23rd I guess. You'll find it. Total answers about 158 or so.