Anti-skate

Audiofeil raised an interesting point about the effective velocity being reduced for the inner groove. When I said earlier that there was no obvious reason why skating force should be different for the inner groove, I did not consider the change in velocity. This is obviously a big difference between inner and outer grooves (funny how things are so obvious once someone else thinks it up).

But, I am less certain about whether the lower inner groove velocity would increase or decrease skating force.

From my own experience, whenever I found asymmetric distortion (one channel more than the other) when playing the inner groove, it has lead me to decrease antiskating. While this suggests that skating forces are lower for the inner groove, it could also be the case that my arm does not apply the same force at all positions and has simply increased antiskating too much for the inner groove position. Greater minds are needed here.

My Moerch DP6 has a string on a spring kind of anti-skate mechanism that is progressive in nature. It pulls on a point attached to the base of the tonearm, so that the force exerted increases as the tonearm base pivots and the arm moves more toward the center.

Basically I've found that setting the anti skate so that that the needle falls exactly in the same groove when raised and lowered again (using an outer groove) sets it pretty much perfectly to my ears. There is virtually no anti skate on the outer groove and a bit more on the inner groove as the tonearm pivots and the anti-skate string/spring is pulled taughter.

Don't know if this is any use to anyone, but I thought I'd share.

Bob

SonofJim...Yup, when I removed the whole device, the sound really popped. I suspect that there is a resonance from the gizmo, like (all?) others which is why Harry doesn't like the devices at all. Never the less...if you find no anti-skate to your liking, (I know it's a pain), but remove it and listen...you can always replace it again.

Hmm,is there any wonder why a good LTT arm sounds so good?

Anti-skate issues? Nope! Inner groove distortions? Nope! Mnay folks going to the lengths to have/experience this kind of music presentation(yeah,it "presents" music a good deal differently than the pivoting crowd,like me,is used to)? Nope!

Folks owning the better Linear Arms selling them soon?

UM, NO WAY!!!

For the uninitiated,go hear a good set-up utilizing a superb LTT arm and be "amazed"!!

Bring familiar LP's,and don't worry about the hassle of traveling, to experience what the best LTT's bring to the table......"You're going to be well rewarded,and you will listen a bit differently to your own system"!

Just imagine:This anti-skate issue is "only" one component of "correct" LP replay.Not to mention tracking error/distortions just vanish with a good Linear Arm,if set up well.

I've heard the benefits of a superior linear design on SO many occassions that I've gotten spoiled,yet still come back to my unipivot....Why?...Because I'm lazy,and freely admit to rationalization,like SO many of us!

The best Linear Arms are costly,and a bit of a hassle to set up,and maintain.What they bring to the table is absolutely "addictive",if you actually have been listening to "good" LP's for a "long" time.

Some,like the Forsell,and "maybe"(it may still be sold in small quantities)the fabulous Air Tangent(some feel this arm was light in bass...."not" if you went the extra mile,and replaced the standard pump,amongst some other things)) are no longer made,but do appear on the used market.....BUY THEM!!!

Then send me a nice bottle of Barolo as a thank you gift -:)

To me,they are like "pre-war" Martin Acoustic Guitars.Once you've heard them "do" their thing,you know it's not going to get any better than this!Especially if you've owned a few pivots over the years,and have spun a load of LP's.

Usually I'd add IMO....This time it's just plain "fact"!

Hear what I'm talking about!Ask a lucky(smart) owner to let you give his rig a listen!

Maybe a nice/classy guy like Albert Porter(I believe he has a Walker)can be coaxed into renting out his listening room and system while he's at RMAF next week? It won't be cheap though -:)

Best

If I remember my basic physics ('ats a real loooong shot) friction is a force applied in direct opposition to velocity. So, less velocity, less friction, less amplitude to the force vector in the inward direction. (see Larryi's post on headshell angle) And, it is somewhat intuitive that if the entire lp surface is moving at the same speed, some little guy (or one of those vw micro-bus players) has to run faster at the outer edge to keep up with his buddy who is running at the edge of the lp label. Crap, just stare at an LP spinning on your table and you'll soon see this.

I'm just surprised as Hell that Audiofeil remembered this fact! (jest kiddin' Bill!)

To take this a step farther, this is exactly why tonearms like the Basis Vector and TriPlanar and probably some others I'm not thinking of, use a fulcrum approach to AS. That is, both of these arms use a device that lifts a weight extended out an arm or lever. At the outer edge the lever is at or below horizontal which is where the opposing force of the weight on the lever is the greatest. As the arm tracks across the LP towards the inner groove the lever is pulled to a higher and higher angle and the force of opposition provided by the weight is diminished in relation to this angle (cos x) of the lever with respect to horizontal. As an angle approaches 90 degrees, or complete vertical, the opposing force of the weight approaches zero.

Anyway, my recommendation is to use little or no AS. Listen for mistracking in the right channel and then apply only enough AS to stop the mistracking. If you can't apply enough AS to counter the mistracking then the LP is possibly damaged. Now try adding a few tenths of a gram in VTF to see if that will stop the distortion. If it does, then go back and let up on AS. I think one can see the process developing here.

But all of this assumes that the stylus is aligned as close to perfect as possible. The larger the error, the more the amplitude of the inward vector. So the goal is to eliminate alignment error which should help eliminate the need for AS.