I bought my (then) mint 2nd hand LP12 about 8 years ago from Axent (just the straight LP12 - no Valhallah or anything like that) with Ittok LV II arm, and last five years with AT OC9 MC cartridge. As my then preamp (Sonic Frontiers SFL1) did not have a phono section, I bought a 2nd hand Linn LK(forget the #s) pre amp from Absolute Sound and thought that matching Linn with Linn I must have the best available vinyl sound. Until I was persuaded, about 6 yrs ago, to take a Plinius Jarrah home to try. The improvement was incredible. After picking my jaw up off the floor I rang the shop to confirm my purchase, and I haven't felt the need to change anything since. Nice feeling after several years of regular upgrading!

After that intro, what I am looking for now in this forum, some advice on a recent problem with my LP12. I cue up the arm over the intro track on the record, release the lift lever, but the arm does not drop straight down - it slowly falls like this - - and if I am not there carefully guiding it, will fall just over the edge of the record. I have carefully gone thru the set up process - setting weight and anti skid (both at 1.5) up again from zero, but the problem persists. Any ideas about what else I can do?

When I had a Tiktok it cued straight down with no noticeable deviation.

 

Check the Linn is on a perfectly level surface.

Then double check the sub-chassis levelness etc.

 

Armlift is not bent ?

 

Arm bearings not sticking ?

 

Isn't 1.5g a bit light for an AT-OC9 ?

Most folks use about 1.75-1.8g.

Thanks Michael. I have reset to 1.8g, problem still occurs. Levels seem spot on, no bends in arm. Don't know about arm bearings - movement appears smooth - can they be lubricated? Just now, when a record finished, I cued the arm up, and as an experiment set anti skating to 0, and the arm of its own volition returned almost to the rest post. I then set anti skate to full, and when cueing up on the other side of the record, the arm now drops straight down! Will experiment further to see which minimum antiskate setting will work, because I assume it may not be best to leave it on its maximum setting?

 

sub wrote:

I cued the arm up, and as an experiment set anti skating to 0, and the arm of its own volition returned almost to the rest post. I then set anti skate to full, and when cueing up on the other side of the record, the arm now drops straight down! Will experiment further to see which minimum antiskate setting will work, because I assume it may not be best to leave it on its maximum setting?

 

That sounds as though there is a fault with the Anti-skate adjustment.

 

Anti-skating, as you probably know, is there to compensate for the force applied by the spinning record to the stylus, which tries to pull the arm assembly across the records surface towards the centre spindle.

 

If you start with the anti-skate set to 0, adjust your tonearms balance so that it sits with the stylus just above the records surface, the arm should not move sideways without a push.

 

As you slowly increase the anti-skate adjustment, the arm should eventually begin to move toward the rest position.

 

I don't think that the arm should ever drop in a straight line when anti-skate is on maximum.

 

If it does, there is a fault which needs to be repaired.

 

Hope this helps.

 

OOps - I've had another look at my experiment. When anti skating set to Off it drops straight down, and when set to maximum it pulls the arm back to the rest post (not the other was round as per my previous post). I've always been of the opinion (can't remember where I learnt it) that anti skate should be set at the same level as the playing weight. I've now got anti skate set at .5 (anymore than that and the arm gets pulled back toward the rest), and playing weight at 1.8g. Doesn't sound right to me, but it works.

I haven't played around with turntables for ages, but I recall that anti-skating should always be set initially to the same as the tracking weight, as they are related.

 

Further adjustment can improve sound quality, but if you have to have the a/s set so low, there's something wrong.

This is why I like the simple 'nylon thread with a weight' arrangement on the Project 9c arm... never had a problem.

 

You may be best to drop the deck into a reputable dealer who can help you sort this out?

Firstly, it is normal for the Antiskating force to pull the arm outwards when the arm is not on a rotating record. So when, as cloth ears explained, the arm is initially balanced, it must be done with zero Antiskating setting...otherwise the arm will float outwards.

 

It sounds to me that you have insufficient or faulty tracking force setting. If you drop the arm using the damped cueing lever, the arm should have sufficient tracking weight on it for the friction (of armtube on the rubber cueing arm) to prevent it from moving sideways.

 

If the arm drops slowly (lifting off the cueing arm & thus floating sideways) then tracking force sounds too low.

 

The Ittok has internal spring-loaded tracking force setting. Personally I always dispensed with this (used zero setting) & moved the counterwt inward (after balancing) to set tracking force, using a Shure Stylus Force Gauge or such.

 

I did it this way for sonic reasons, as I am a paranoid audio nut

 

Check tracking weight, somehow.

Cheers, Owen

I usualy send Aucklanders with LP12 issues to go and see John Vivian at Shore Hi-Fi in Takapuna. He's very good with all things to do with Linn turntables.

Hi Owen, if I understand you correctly, I need a tracking force gauge to ensure correct T/F has been set. I guess on a delicate instrument like this that is over 20 years old I may not be able to trust that the 1.8g I set on the dial is actually 1.8 - especially since I have to set A/S to .5 to get the arm to drop vertically when cueing. My setting up process is to set both gauges to 0, balance the arm in a horizontal "floating" position using the counter balance. When that is done, I then set T/F and A/S. I scored the AT OC9 in a box lot at an auction for $10 some time ago so it did not have any set up instructions with it (I took it to Absolute Sound & they checked it under their microscope to ensure it was OK before I used it), so until Micheals advice have used a generic T/F of 1.5g. Looks like another purchase is on the horizon - I note some one is selling gauges on trademe, but I think they can be sourced cheaper from the Needle Dr.

The OC9 has a recommended tracking force of 1.25-1.75g, so 1.5g would be fine. I normally run my OC9 a little heavier than that (aroun 1.7g from memory), more to ensure that it is more secure in the groove than anything else.

Hi sub,

 

Yup, USD25 for the Shure gauge, is all you'll need... get one before the NZD falls again

 

Using a gauge like this, even if the arm's VTF mechanism has become inaccurate, you can still use the arm. It's a pretty good arm.

 

Your setup methodology sounds OK. Balancing, as per cloth ears, should ideally be with stylus floating at or near record level.

 

Another thing, if the VTF is somehow way too low, I would expect it also to sound a bit odd, mistrack probably...??

 

Cheers, Owen

 

sub wrote:

My setting up process is to set both gauges to 0, balance the arm in a horizontal "floating" position using the counter balance. When that is done, I then set T/F and A/S.

 

You should also ensure that the arm is level when the needle is on the record. If the arm was set up for a different cartridge you may find that the angle is way off. To adjust the angle, use an allen key to loosen the hex screw on the arm base and adjust the height while supporting the arm (don't let the arm drop suddenly when you loosen the screw).

Thanks Guys, Am ordering a stylus gauge. Owen - no mistracking, in fact sounds just fine (perhaps the 1.8g playing weight I have now set sounds a little more "full" that when I had it set at 1.5, so will be interesting to check things out with the gauge when it arrives).And Hi newbilong, yes I made that adjustment when initially installing the OC9 some time ago. Will post when the gauge arrives.

Cheers - Sub

Hi Guys, the Shure stylus gauge arrived today - only five days for delivery from USA - not bad. The price was $US25, but because they wanted $US27 for Courier Post, I decided to order a new AT OC9 (The Needle Dr currently has them marked down from $US400 to $US289) at the same time to make the postage more cost effective. Haven't got the credit card statement yet, so not sure how much that will translate into $NZ!

Played with the gauge tonight. I had to set the TW at 1.7 on the Linn (AS set to 0) to get it weighing 1.5 on the scales. Then set AS to 1.5 and everything works fine. Will play around with a slightly heavier TW as recommended above. Thanks again for the advice.

Sub:)