Some questions re: tracking weights and cartridges...

Posted by: Top Cat on 11 February 2002

Hi folks.

Wanting to fine-tune my turntable, tonight I was mucking around with the tracking weights for the cartridge. The spec for my cartridge states 3g as the 'nominal' weight, but included with the cartridge was its test sheet (showing the unique frequency responses, channel seperation for my specific cartridge, as measured by QA at the cartridge manufacturers). Along with all the fancy graphs and so on was a recommended tracking weight of 2.5g (max) to 1.8g (min). Fair enough, although I'm surprised it's as low as this, as it's quite a deviation from the published spec.

Anyway, to business. Due to the unusual nature of my tonearm, I have interchangable counterweights: a 2g one, a 4g one and a 6g one. My dealer had the 4g one fitted, but I wondered that if my cartridge wants to track at 2.5g(ish) then isn't putting a 4g counterweight causing the cartridge to be under insufficient loading?

Maybe I'm being thick here, but surely a 2.5g tracking weight balanced by a 4g counterweight is a bit odd? Am I forgetting something really fundamental here, or is my hunch that the 2g counterweight would be better one worth investigating?

More to the point, I'm assuming that there are no other weight variables to take into consideration. VTA is by the book plus a tiny margin (I found the standard VTA a bit 'lightweight' sounding; again, does this point to the 4g:2.5g imbalance?

Can anyone who knows about these things shed some light onto my question?

Ta,

TC '..'
"Girl, you thought he was a man, but he was a Muffin..."

Posted on: 11 February 2002 by Top Cat

If the ideal counterweight is somewhere between the 2g and 4g weights, which would be better for general use - a little underweight (4g cw, i.e. > optimal tracking weight) or a little overweight (2g cw, i.e. < optimal tracking weight)

Or is there something else that I've forgotten...???

Sorry about the 'complexity' of my question!

TC '..'
"Girl, you thought he was a man, but he was a Muffin..."

Posted on: 11 February 2002 by Top Cat

Okay, one more:

Again due to the unusual nature of the 'vestigial' tonearm of the tangential arm on my deck, the tonearm counterweight can be located at any point between the back of the arm and the 'pivot' (beyond which lies the cartridge). Where is the best place to place a counterweight - further away from, or closer to, the pivot point?

TC '..'
"Girl, you thought he was a man, but he was a Muffin..."

Posted on: 11 February 2002 by Paul Ranson

quote:
Where is the best place to place a counterweight - further away from, or closer to, the pivot point?

It depends what you want your tracking weight to be.....

Surely this arm has a handbook?

Paul

Posted on: 11 February 2002 by Top Cat

Yeah, it has a handbook, but it's beyond anything I've ever seen - absolutely terrible. Even the diagrams are different to the tonearm I have - Clearaudio lose points for documentation, for sure!

I've been trying to make sense of it, but it simply glosses over counterweight settings - something like 'use a most appropriate of weightn for you cartridge weightn' (sic)!!!

TC '..'
"Girl, you thought he was a man, but he was a Muffin..."

Posted on: 11 February 2002 by Paul Ranson

I think you need a stylus balance, (buy one here), otherwise you're working in the dark.

Being old and prejudiced any tracking weight over 2.0g or below 1.5g seems wrong.

I've no real idea of the layout of your arm, but if you have pickup/pivot/balance-weight then moving the balance towards the pivot increases tracking weight. Because the arm is very short and light different counterweights may be necessary to bring differing cartridges into balance.

Paul

Posted on: 11 February 2002 by Mark Dunn

Hi Top Cat:

Can you post a piccie of your arm so we can get a better idea of your conundrum?

Best Regards,
Mark Dunn

Posted on: 11 February 2002 by Martin Payne

quote:
Originally posted by Top Cat:
Maybe I'm being thick here, but surely a 2.5g tracking weight balanced by a 4g counterweight is a bit odd? Am I forgetting something really fundamental here, or is my hunch that the 2g counterweight would be better one worth investigating?

TC,

where to start?

Can't quite picture your arm from your description (quick blast on the forum before I go to bed, so I'm not at my best).

Start with a 'standard' arm configuration - cartridge on the end of a long stick, counterweight on on a short stick on the other side of the bearings.

Fundamentally, this is a lever. Remember Archimedes:- "Give me a lever long enough, and a place to stand, and I can move the world."

If the c/w is 1/10th the distance of the bearing from the cartridge, then it will need to be 10x the weight in order to balance out (cartridge floats in mid-air). Of course, the arm-tube has to be balanced out by the c/w, too.

On my Ekos, once you've found the static balance position, the tracking weight is then set with a dial & spring.

Sound like your is quite different, though? 3g sounds much higher than I'd expect from my meagre experience with cartridges (K9, Troika, various ATs).

cheers, Martin

Posted on: 12 February 2002 by Top Cat

Hi folks, thanks for your input so far. To clarify things a bit, here's a couple of images which will give you an idea of where I'm coming from with the arm (it's difficult to describe but much easier to see!):

This is my TT, and an arm fairly similar to my own (but not the same):

And here's the vestigial tonearm (best picture I could find)

As you can see from the second image, there is a lot of scope for moving the counterweight backwards or forwards, as it's a slightly unusual tonearm relative to things like Ittoks, RB300s and so forth.

TC '..'
"Girl, you thought he was a man, but he was a Muffin..."

Posted on: 12 February 2002 by Steve G

quote:
Originally posted by James:
And I thought my ARO was fiddly. Tell us, TC, do you idolise Lara Croft or does the Clearaudio really make better music than the trusty LP12?
I'm betting that you'll soon do a Dev and buy an LP12 once the novelty wears off.

I've heard TC's system and the turntable does sound very good. I've never heard an equivalent priced LP12 so can't comment on whether it's better or worse however.

Regards
Steve

Posted on: 12 February 2002 by Top Cat

quote:
And I thought my ARO was fiddly. Tell us, TC, do you idolise Lara Croft or does the Clearaudio really make better music than the trusty LP12?

In the context of my system, considerably so. I had an LP12/Lingo/Aro/Asaka with the usual Mana mods (3M feet) at Phase 7, which really sounded great - by far and away the best LP12 I've ever heard, bar none (but then I've never heard a fully-Naimed LP12, or a Ninja one either).

However, the Clearaudio was a big surprise. I expected it to sound like it looks - a bit clinical and soulless. I expected to buy another LP12 (fully Naimed) or a P9, but in comparison to the P9 the Evolution utterly destroyed it on everything but sheer speed, the honours to which went to the P9. But timing, musicality, tonality, listenability and fun accolades went to the Lara-lite!

quote:
I'm betting that you'll soon do a Dev and buy an LP12 once the novelty wears off.

I really really like the LP12, there's nothing like it for secondhand value - £300 will get you a servicable Valhalla deck and it will rock. However, given that I had no choice but to buy new (insurance claim), I had the choice of £3500 for a full monty LP12 (ouch!!!!), or I could look around and see what the competition had to offer. As mentioned before, I'd never had the chance to really hear the competition at that level due to budgetary constraints, but all of a sudden I had an excuse and around four grand to spend. It turned out that the Clearaudio and the full-monty Xerxes were the most musical decks, with the LP12 close behind the Xerxes and the P9 lagging a bit. The P9 was worse than I expected and the P25 better, although still some margin behind the P9.

Would I do a Dev? No, I really don't think so. Whilst I won't say a bad word about the LP12, it just is the case that the plastic-fantastic is a considerably better deck to my ears.

I might buy a s/h LP12 for the second system (Nait-2-based) if a nice one comes my way, but I know that the LP12 would need to be absolutely maxed out to be any competition for the Evolution. I don't know why this should be but having owned both (LP12 for 3.5 years) I feel qualified to state this opinion...

TC '..'
"Girl, you thought he was a man, but he was a Muffin..."

Posted on: 12 February 2002 by Mark Dunn

Hi Top Cat:

Cor blimey guvnor! Call the Tate immediately, someone's 'ad it on their toes with an exhibit!

Seriously, I saw a similar Clearaudio in Las Vegas a couple of years back and it was sounding good, - even in the hotel room.

If it were me, I'd buy a Hi-Fi News test record (mostly designed by Len Gregory, 'The Cartridge Man'). It has bands for finding the arm/cartridge resonance. Use the weight that gives you a resonance between 9Hz and 12Hz. If more than one weight will do this (dependent on different positions along the arms length) my GUT feeling would be to go with the one that gives a result when closest to the 'pivot'. However, it's definitley worth listening to each solution to see which you like the best.

Best Regards,
Mark Dunn

Posted on: 12 February 2002 by Peter Stockwell

Under static conditions the mass of the cartridge multiplied by the distance from the pivot must equal the mass of the counterbalance multiplied by the distance from the pivot.

But, under dynamic conditions the total moment of inertia (is that right ?) has to be considered, and I believe it is calculated by:

m * d² where is m is mass and d is the distance from the pivot.

So it would appear that a heavier counterbalance is better than a lighter one, because it will be easier for the arm, and the stylus, to track any warps and other record nasties.

Peter

Posted on: 12 February 2002 by Rob Doorack

TC, be sure to measure the tracking force at the level of the record surface - not with a scale sitting on the platter - or your measurement will be wrong. You might have to make a stack of books or something next to the platter and set your VTF scale on that.

Posted on: 12 February 2002 by Eric Barry

Well, if the weight is heavier, it can be closer to the pivot, which will lower the rotational inertia. Good or bad, I don't know--with pivoted arms that's generally considered a good thing, and I don't know why it wouldn't be with the Souther arm either.

To the sceptics, Clearaudio cartridges do track at very high weights. However, you have to remember that the stylus pressure is force divided by area of contact, and today's advanced stylii have much greater area of contact than the conical or eliptical tips of yore, so tracking force should not be a problem. Anyway, several serious collectors/audiophiles I trust have used Clearaudio carts for some time, so I wouldn't worry about the record wear. I can't say anything about the sound quality--but I don't think wear is a problem.

--Eric

Posted on: 12 February 2002 by Mike Sae

Does this mark the return from your "retirement"?

Serious question,

AFAIK, the Clearaudios don't come with dustcovers. Does dusting the plinth make horrendous swirl marks in the plexiglas?

Also, have you heard the baby Champion? If so, how do you rate it against the P25?

Posted on: 13 February 2002 by Top Cat

Seriously, though, I've taken to simply brushing any dust off with a clean cloth, no polish or similar. I've also taken to leaving an unwanted LP on top of the platter to keep dust off. Saying that, it's not been too bad for dust so far.

My retirement was partly due to losing my ADSL access and not having ready internet access, partly for a chance to cut back on my forum addiction and partly because I got fed up dealing with a couple of really prejudiced individuals who wanted to make mountains out of molehills and spread a lot of lies around. Ultimately, I decided that the vast majority of folk here were fine folks indeed, and didn't want to miss out on their ideas and experiences due to an ignorant few.

Getting back to hifi, yeah, really pleased with the deck, and have taken to fiddling with its setup - probably a mistake, but my dealer is happy to jump in and help if it all goes horribly wrong!

TC '..'
"Girl, you thought he was a man, but he was a Muffin..."

Posted on: 13 February 2002 by Top Cat

Didn't get a chance to hear the Champion, but felt the P25 represents a lot of sound for a sensible price. Was disappointed with the P9 (expected more of an improvement over the P25 than it delivered) but the P25 is a cracker at its price. Still think a s/h LP12 makes a better buy, but my experience in auditioning various decks hit it home to me that the LP12 is not the only deck worth considering by a long shot, and can be bettered at its new price (if not its s/h prices)

TC '..'
"Girl, you thought he was a man, but he was a Muffin..."