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Alex_UK
16-09-2009, 09:45
I need to get both my turntables setup properly - don't have a gauge, they appear to be expensive - any reason why I couldn't use one of these? http://cgi.ebay.co.uk/Precise-Digital-Jewellery-Pocket-Scale-0-01g-x-50g-case_W0QQitemZ270456843888QQcmdZViewItemQQptZUK_BO I_Medical_Lab_Equipment_Lab_Equipment_ET?hash=item 3ef87bee70&_trksid=p3286.c0.m14

Or, any other suggestions (I vaguely rememeber Marco mentioning a digital food scale from a Pound shop - but this looks like it would be smaller and easier to use?)
(http://cgi.ebay.co.uk/Precise-Digital-Jewellery-Pocket-Scale-0-01g-x-50g-case_W0QQitemZ270456843888QQcmdZViewItemQQptZUK_BO I_Medical_Lab_Equipment_Lab_Equipment_ET?hash=item 3ef87bee70&_trksid=p3286.c0.m14)

Dave Cawley
16-09-2009, 09:49
The magnets in your cartridge may well upset the instrument.

Dave

Marco
16-09-2009, 09:54
Why not, Alex... As long as it's non-magnetic, you should be fine :)

What a bargain, eh, compared to an 'official hi-fi design'? It’s quite elegant looking, too.

It always amazes me how products already sold in other markets gain a zero (or zeros) on the end of their price tags as soon as they are 'designed' (or should that be labelled) for the hi-fi market.... :mental:

Marco.

Marco
16-09-2009, 09:56
The magnets in your cartridge may well upset the instrument.


Hi Dave,

Would that not also apply to the ones from the Pound Shops? If so, it's not an issue with mine :)

Marco.

Dave Cawley
16-09-2009, 10:00
You just can't tell!

Dave

Alex_UK
16-09-2009, 10:01
Cheers chaps, must we worth a go then, for the money - I can always bung it back on ebay if it doesn't work (and I can be bothered about a tenner...) I'll order one and report back.

Ammonite Acoustics
16-09-2009, 10:14
I have the one sold by Origin Live, Roksan etc, and am happy with it.

What I would like to know is the importance of the height of the measuring surface. The OL gauge is set to roughly LP height, but that cheap eBay one is clearly set much higher. Does it matter; and if so is it arm-dependent? Where do potential errors arise, if at all?

As I already have a suitable gadget, it's of academic interest to me, but for someone wishing to buy one, a technical explanation would be useful, if anyone has the expertise to comment!

Will
16-09-2009, 10:15
No problems with my scales, stainless steel top plate.

Stick some polystyrene foam (Erase Away from Wilkinsons) on the top plate with double sided tape, this hold the stylus and cleans it at the same time.

Dave Cawley
16-09-2009, 10:19
Hi Alex

How will you know if the magnets in your cartridge are affecting the reading?

Regards

Dave

Will
16-09-2009, 10:49
With 1/4 inch of foam the magnet adds 0.03grams.

..

DaveK
16-09-2009, 10:57
Hi Guys,
Just my two penn'orth: -
I bought a very similar one, similar shape, design and size (as far as I can tell), but no leather case - mine has a clear plastic hinged lid and a couple more buttons - from Maplins for either £10 or £20, can't remember.
I'll try to answer points raised by others:
1) effect of cartridge magnet - tried mine with fridge magnet and no attraction so cartridge magnet shouldn't have any effect.
2) height of scales - may be coincidence but mine is almost exactly the same height as the difference in height between top surface of LP on platter with mat in place, and the top of the upper surface of the deck, so placing it under the cartridge rest position and lowering the tonearm on to it gave the 'weight/force' at the correct height, give or take a gnat's cock. (technical term ;) ).
And, most important, I'm happy with the resulting sound.
Cheers,

Dave Cawley
16-09-2009, 10:57
Every magnet? How could that be? edit: Fridge magnet test is a good idea!

The Grand Wazoo
16-09-2009, 11:01
A note of caution, there Will.
That stuff can rip your stylus off if you're not careful.
I use it & have done for years, but you should take extreme care, lock the platter & only use the lift/lower device.
If it's the same as the Magic Eraser I use, it's actually not polystyrene foam, it's melamine foam & the reason it's so good at cleaning is that the structure of the material has millions of tiny barbs on it. But a sideways movement when your stylus is embedded in it can prove that the gripping power can be stronger than the holding power of your cartridge makers glue!

Apart from that, it's fantastic stuff!

So are the 'sticky hands' :
http://theartofsound.net/forum/showthread.php?t=551

Post No. 5

Will
16-09-2009, 11:10
Yes Melamine foam and I should have said use a vertical dip into the foam,
very good as it keeps fingers away from the stylus.

..

Alex_UK
16-09-2009, 11:24
Hi Alex

How will you know if the magnets in your cartridge are affecting the reading?

Regards

Dave

Put something small on the scale, around the same size - then slowly move cartrige/headshell into close proximity - if the weight doesn't change, then it should be fine, I would think.

Dave Cawley
16-09-2009, 11:26
OK, let us know the results?

Thanks

Dave

Marco
16-09-2009, 12:14
Put something small on the scale, around the same size - then slowly move cartrige/headshell into close proximity - if the weight doesn't change, then it should be fine, I would think.

Also, try setting VTF first using the arm mechanism, noting where the counterweight balance is positioned relative to the reading on the dial (presuming your CWB has such a dial), or just note the position of the CWB on the armtube at the given setting, then pop the stylus on the digital scales, and if the VTF reading is in the same ballpark you'll know that the scales are doing their job correctly...

In my experience, short of the accuracy of a mechanism like that on an SME, the digital scales should provide a more accurate reading than on most arms of what the VTF being applied *actually* is :)

Marco.

DaveK
16-09-2009, 12:25
All right, I'm a novice at this, which might explain something, but I was certain that I had set my VTF correctly using the counterweight but the scales showed that I was a whole 1 grm out - not bad when aiming for 1.75 grm :doh: :doh: :doh:
Cheers,

Marco
16-09-2009, 12:28
Dave, you obviously hadn't zeroed it correctly, 'tis all! :eyebrows:

I'll show ya how properly at Owston :cool:

Marco.

Cotlake
16-09-2009, 18:30
I have a set of 'UK Scales' bought cheaply off ebay. They advertise as non-magnetic which I've found to be untrue. As suggested previously, you can check but don't need anything pre-weighting the scales because they will record a negative value on weight if you know what I mean. Therefore, slowly lower the stylus towards the weighing plate and if there is magnetic attraction you see a minus or negative reading appear which will increase the closer you get, but of course will read positive once contact and weight is applied. The way around it is to either have something of sufficient thickness already on the scales which are zero'd or to use the popular bent credit card method where the main area of the card sits on the scales with a section of card overhanging the plate to the side onto which you rest the stylus.

Regards,

Greg

Marco
17-09-2009, 06:41
...or to use the popular bent credit card method where the main area of the card sits on the scales with a section of card overhanging the plate to the side onto which you rest the stylus.


Yup, that's what I do - it's undoubtedly the best way :)

Marco.

Clive
17-09-2009, 07:00
Here's what I lashed up, 2 pieces of plastic card, double sided tape and its setup to weigh at record height.

http://i43.photobucket.com/albums/e359/cmeakins/0909170003.jpg

DaveK
17-09-2009, 07:53
Clive,
If I surmise correctly how your device works I have the following question.
A long, long time ago I studied at a very basic level the subject of Mechanical Engineering and I seem to recall the force magnifying and reducing effects of levers. Is there any danger with your set up that applying the force in one place and measuring it somewhere else could be influenced by this lever effect?
Are there any proper Mechanical Engineers amongst us that could comment authoratively?
Cheers,

Clive
17-09-2009, 08:15
Dave,

A 1p should weigh 3.56g, a 2p 7.12g.

My scales over a few samples come in at 3.54g and 7.10g respectively so maybe it shows 0.02 light.

I have a 50g calibration weight that does read 50.00g but also varies between 49.99 and 50.02 due to it bending the plastic.

Theory's all well and good but there's nowt like a practical test!

Clive

DaveK
17-09-2009, 09:27
Dave,

A 1p should weigh 3.56g, a 2p 7.12g.

My scales over a few samples come in at 3.54g and 7.10g respectively so maybe it shows 0.02 light.

I have a 50g calibration weight that does read 50.00g but also varies between 49.99 and 50.02 due to it bending the plastic.

Theory's all well and good but there's nowt like a practical test!

Clive

Hi Clive,
Well that puts that to bed nicely then - theories are a fine 'seed' for practice, full stop.
Cheers,

REM
17-09-2009, 10:08
I was going to post earlier about using a 2p coin as a callibration weight, a new one should be exactly one quarter of an ounce, but decided against it as admitting such knowledge may lead to embarrasing questions;):smoking:

Alex_UK
17-09-2009, 17:47
Well thanks all for adding your 3.56g worth! ;)

That is very useful though, for calibrating, cheers.

DSJR
17-09-2009, 21:14
On US ebay a few days ago, there was the old AR stylus pressure gauge for the old XA turntable and arm. brilliant it was - plastic moulded scale with accurate and consistant weights and accurate to 1.4 gramme as I don't remember an 1/8 gramme weight. Good enough for most cartridges out there..

They'll probably charge a small fortune for it, but the little Ortofon balance is very accurate too. I mean, if Naim use it for the ARO then it must be good :)

blake
17-09-2009, 23:46
For between $50-$70, the Canrong scale (marketed by Origin Live, Acoustech, etc. at much higher prices) is a bargain IMO.

It is definitely non-magnetic, deadly accurate to within .007 gram (as confirmed by my wife who is a research technician and tested it against some very sophisticated lab scales for me) and has a weigh platform that very closely approximates the height of an LP (it is just a touch higher so best to set tracking force approximately .020-.040 higher when you set tracking weight using the scale) and can be easily used right on the platter without doing credit card tricks etc to approximate the height of an LP on the platter itself (which is critically important).

The stock batteries which came with mine were garbage, but replacement batteries lasted well into the 2 year range before crapping out.

Cotlake
18-09-2009, 21:29
They'll probably charge a small fortune for it, but the little Ortofon balance is very accurate too. I mean, if Naim use it for the ARO then it must be good :)

That is probably the most naive and in consequence ignorant statement I've read from a dealer in a long time. Why do you think that if Naim rate it it is good? Get real!

Alex_UK
18-09-2009, 21:44
Um, isn't that called humour? I read the ":)" as being ironic - :confused: sure Dave can speak for himself though and confirm or deny.

Cotlake
18-09-2009, 21:56
You might well be right. I didn't see it that way but maybe I need to lighten up. It's been a bad week.............

Alex_UK
18-09-2009, 22:01
Sorry to hear that Greg - hope things improve for you - and the problem with this 'ere internet is that it is very hard sometimes to get the intention of a post - it will always happen! And anyway, I may be wrong! ;)

Alex_UK
18-09-2009, 22:06
Just to go back to the scales, I ended up ordering a slightly different one, mainly because this one http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290350030467&ssPageName=STRK:MEWNX:IT (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290350030467&ssPageName=STRK:MEWNX:IT)uses AAA batteries instead of those silly "button cells" (is it just me, or has the "links" tool gone to rat-sh!t?) - plus only six quid inc p&p. Update to follow when received.

kcc123
20-09-2009, 09:44
That is probably the most naive and in consequence ignorant statement I've read from a dealer in a long time. Why do you think that if Naim rate it it is good? Get real!

I have quite a few of those Stylus force gauges, including the Ortofon and Shure. I am sure that the Ortofon balance is not the most accurate and my Technics SH-50P1 electronic stylus pressure gauge which I bought at Tottingham Court Road in London ages ago is definitely better. But it is still not as accurate as the one that I currently use:-

http://i33.tinypic.com/2zqhgyq.jpg

Alex_UK
30-09-2009, 08:23
Just to go back to the scales, I ended up ordering a slightly different one, mainly because this one http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290350030467&ssPageName=STRK:MEWNX:IT (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290350030467&ssPageName=STRK:MEWNX:IT)uses AAA batteries instead of those silly "button cells" (is it just me, or has the "links" tool gone to rat-sh!t?) - plus only six quid inc p&p. Update to follow when received.

Just beware if anyone follows my link - although the seller has stated the item location as "London, UK" it appears not to be true - actually a Hong Kong seller! :steam:

Scales not received after nearly 2 weeks, I expect they will turn up but I will be complaining to ebay about the misrepresentation...

DaveK
30-09-2009, 09:01
...... but I will be complaining to ebay about the misrepresentation...

Hi Alex,
IMHO, based on personal experience, including a current problem whereby they have charged my PayPal account for faulty/not received items (1 each) when I am NOT the seller, complaining to eBay is a complete waste of time - they are the most uncaring, unresponsive, difficult to effectively communicate with organisation it has ever been my misfortune to be involved with. As long as their excessive rake-offs keep rollong in they don't give a shit - just my opinion of course, but I've heard many similar comments.
Good luck!

Dave Cawley
30-09-2009, 09:03
The one you link to (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290350030467&ssPageName=STRK:MEWNX:IT) is 0.1gm resolution. Normally on digital devices there is +/- 1 digit uncertainty which could at worst be effectively 0.2gm, a bit high.

The one King shows is 10 times better. My reservations on anything digital still holds though. Magnets and metal.....

Regards

Dave

Alex_UK
30-09-2009, 09:25
The one you link to (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290350030467&ssPageName=STRK:MEWNX:IT) is 0.1gm resolution. Normally on digital devices there is +/- 1 digit uncertainty which could at worst be effectively 0.2gm, a bit high.

The one King shows is 10 times better. My reservations on anything digital still holds though. Magnets and metal.....

Regards

Dave

Agree totally, but it's a) miles better than "it's going round and round and a noise comes out" which is currently how it is setup, and b) is cheap, for an experiment. Except if it never turns up, of course! :doh:

Nigel
30-09-2009, 14:47
I bought the one you recommended in the first instance, Alex UK. Think it's pretty good. It came after a few days, had to buy a battery though & a 50g weight for calibration.

Nigel
30-09-2009, 14:55
Having said the above, my thoughts are, if your in the tracking force range of the cartridge as recommended by the manufacturer, one should simply set the optimum force by ear. I then set the anti skate using the back of a flexi disc. A Max Webster freebie given out at Rush concerts on their UK Hemispheres tour, lol. I picked up a good few at the time.

DaveK
30-09-2009, 16:35
I bought the one you recommended in the first instance, Alex UK. Think it's pretty good. It came after a few days, had to buy a battery though & a 50g weight for calibration.

Hi Nigel,
Only trying to be helpful, not clever, but I spent the first 10 years of my working life weighing out sub-1grm quantities for analysis purposes. Just because your digital scale gives you an accurate reading against a 50grm weight means very little in the context of single figure grm weights. IMHO you would be better off checking it by weighing 1p and 2 p pieces - I am reliably informed that, ex-mint, they weigh 3.5 grm (1/8 oz) and 7 grm (1/4 oz) each, respectively, much nearer the range of VTF that you are checking, I suspect.
Hope this helps.
Cheers,

Dave Cawley
30-09-2009, 16:58
Linearity, resolution and accuracy are all a somewhat movable feast.

Dave

Nigel
01-10-2009, 00:05
Appreciated DaveK. I only purchased said weight because that's what the scales instructions required for so called precise calibration, the maximum weight they can take.

Barry
01-10-2009, 14:14
Here's what I lashed up, 2 pieces of plastic card, double sided tape and its setup to weigh at record height.

http://i43.photobucket.com/albums/e359/cmeakins/0909170003.jpg

Why bother?

Out of curiosity I measured the thickness of my 'flat bed' stylus scales (similar in style to yours) as 13.5mm. For any cartridge mounted in a nominally 9" arm, the error due to the difference in thickness between the scales and an LP, will result in the scales underestimating the tracking force by less than 0.2%.

Even for a tracking force of 3g, the 'error' is 6mg, well within the accuracy of the scales themselves. Most digital scales have a resolution of 0.01g or 10mg; their accuracy is unlikely to be better than this.

Some digital scales have a resolution of 0.001g; in this case the accuracy is most likely no better than 10x this amount (certainly no better, considering how cheap they sell for).

Concerns over the accuracy of calibration weights is also misplaced. I also use a Mitchell Transcriptors balance (where incidently the stylus pad is at roughly the same height as that provided by an LP). To use the Transcriptors balance, the counterweight on the beam is adjusted to balance the desired tracking force established by a set of 'calibration' weights. The maximum force that can be so set up is determined by using the full set of weights: 2.65g. Years ago I weighed these using a precision chemical balance and found that the total weighed 2.675g, that is an error of just under 1%.

For a typical tracking force of 1.5g, the error would be + 0.55%, or 8.3mg.

I think people are worrying needlessly.

Regards

Regards

Marco
01-10-2009, 14:33
I spent the first 10 years of my working life weighing out sub-1grm quantities for analysis purposes...


Sounds intriguing, Dave. Have you still got contacts? If so, put me down for an ounce of Mexican Black, baby! :peace:

;)

Marco.

Barry
01-10-2009, 15:11
Sounds intriguing, Dave. Have you still got contacts? If so, put me down for an ounce of Mexican Black, baby! :peace:

;)

Marco.

Marco! I thought you were a man of taste and sophistication?

It ought to be Paki Black, Golden Leb or Nepalese Blue. :smoking:

Luv and Peace Man

Marco
01-10-2009, 15:35
Mexican has a soupçon more 'spice', muthafukka, and when that trip kicks in she gets real evil on yo' ass and takes you to da promised land... :eyebrows:

But yeah man, I also digs the Nepalese Blue. Dat's some prim-o shit :smoking:

Marco.

REM
02-10-2009, 07:32
Proper Sputnik that's the stuff, not forgetting the Thai Sticks, sometimes wonder how I ever managed to remember anything about them:lol:

jandl100
02-10-2009, 08:43
I've tried a couple of those cheap digital scales. Both gave very inconsistent results - sometimes varying from one measure to another taken a few seconds later - I gave up with them. I just didn't trust them.


the little Ortofon balance is very accurate too.

Yup, that gets my vote, too. I compared the little Ortofon with a Shure balance and they gave identical results, consistently. Good to 0.1g which is good enough for me. Why pay more?

Dave Cawley
02-10-2009, 09:15
I've tried a couple of those cheap digital scales. Both gave very inconsistent results - sometimes varying from one measure to another taken a few seconds later - I gave up with them. I just didn't trust them.

Exactly, resolution and accuracy, not the same thing, but no one wants to understand!

Dave

Marco
02-10-2009, 09:25
I don't disagree either. I think the point with the cheapo scales is that it's a bit hit and miss (as you'd expect at the price) as to how effective they are.

All I can do is speak from my own personal experience and say the ones I've been using now for over 2 years are accurate and reliable, so it's simply a case of sucking it and see... You might be lucky or you might not - it's as simple as that.

For a pound one can afford to speculate! :)

Marco.

jandl100
02-10-2009, 10:22
I've tried a couple of those cheap digital scales. Both gave very inconsistent results - sometimes varying from one measure to another taken a few seconds later - I gave up with them. I just didn't trust them.

Exactly, resolution and accuracy, not the same thing, but no one wants to understand!

Dave

Aw shucks! I do, Dave. :kiss:

btw - I said 'hi' at the National Show last weekend, but you were so busy bitching about your nametag in the UKD room you didn't hear me! :(

DaveK
02-10-2009, 10:40
Hi Guys,
I'll put my two penn'orth in again, for what it's worth - perhaps more welcome in some areas than others ;) .
Got mine from Maplin's a few weeks ago but can't see them on their site now. They cost either £16 or £20, (can't remember :doh: ), all but 1p, they are backlit a lovely blue colour, weigh in grms, ozs, ct and g (?), and accurate and repetetively so when weighing 1p, 2p and 50grm, with a resolution of 0.001grm AND are totally non-magnetic !
Might be a bit cheaper than some with a fancy hi-fi badge on them, if Maplin's still have them available.
Cheers,