tone arm with 10gr mass with 15 gram weight cartridge?

With that tonearm effective mass plus screws and that cartridge weight you should look for a cartridge with 15cu compliance to get approx 8,15hz resonant frequency.

Anything between 8-19cu would be ok, having a range of resonant frequency between 7-12hz.

Make sure though that counterweight is ok to balance the arm.

thanks petg60
 those things are a bit confusing, since difference producers use difference values .
the values of compliance i saw are for example : 28 micron/nM/
or in some other place

so how should i translate it to your suggestion? 
from what i read the recommendation for a 10gr arm is cartridge with high compliance.
 "Low mass arms mate well with both moderately high and very high compliance phono cartridges".
and what about the cartridge weight to match the arm mass?

Some manufacturers use "compliance unit" or CU as simpler abbreviation, but it means exactly the same thing as the others.

what is important = Resonance frequency within 7-12Hz, mostly it would do the trick. (The RF has to fall down into a precise interval of frequencies: some say between 8 -12 Hz, but reasonably it would be better between 9 -11 Hz).

And yes the general rule is:

a moderately high or a very high compliance cartridge to a low mass arm (up to 10gr).

a moderate to low compliance one to a moderate mass tonearm (11 -20gr).

(Screws are always added to the arm mass - something between 0,5-1gr).

A cartridge having 5-10cu is considered a very low compliance cartridge, a range between 10-20cu is medium compliance, and values above 30 suggest a very high compliance.

and what about the cartridge weight to match the arm mass?

Make sure though that counterweight is ok to balance the arm.

but how do i convert cu to the values that manufactures give?
and what is the effect of the cart weight?

μm/mN=...X10-6cm/dyn=cu

effective mass of tonearm, cartridge mass and cartridge compliance, should produce the desired resonance frequency.

and at the end of the day if sound quality is good (most important) then you forgett all the formulas.

If you are using a Japanese cartridge you will have to double the value from 100hz to 10 hz!

For example: Say we have an arm of with a published Effective mass of 12 grams and a Japanese cartridge weight of 10 grams, with a compliance of 5cu/dyne/100 Hz. Effective Mass of the arm is another topic in its own right and often not published by the arm manufacturer or not published accurately. But for our example we are using a trusted arm manufacturer with good engineering design. We want to know the RF of the tonearm/cartridge combo. The first thing we have to do is to transform the compliance from 100 Hz to 10 Hz by doubling the value of 5, which will become 10. Next we will add up the different masses: 10 g (stylus) + 12 g (arm) +1 g (screws) + other things (like finger lift, in this case let us say they are zero) = total 23 g. Then we multiply 10 x 23 = 230 The square root of 230 is around 15.17. Finally: 159 ÷ 15.17 = 10.48 Hz, a value that places itself in the desired interval of 8 -12 Hz. Another quick way to check compatibility is to plot the predicted resonance using the graph below. Add the weight of cartridge and screws to the Effective Mass of the Arm (manufacturer should publish this). Look across to the Dynamic Compliance (manufacturer should publish this) and hopefully it falls somewhere in the 8-12hz zone.

Here is a calculation chart!

http://www.mh-audio.nl/Calculators/RF.html

Just do it.

Keep in mind that any published figure for tonearm effective mass must be accompanied by some other information, if we are to make sense of it. We need to know whether the published figure includes a "typical" cartridge and the mass of the OEM headshell. As soon as you use a different aftermarket headshell, the EM would be altered. If your cartridge is unusually heavy or light, that too might change the result. Every single cartridge is not going to have a compliance exactly as stated by the maker of that particular cartridge; there can be significant sample to sample variation. Finally, the counter-weight has a variable effect on EM; the CW adds to EM in relation to its weight times the square of the distance between its center of mass and the pivot.  So to minimize EM, you want the heaviest CW that works to counterbalance, so it can be as close as possible to the pivot.  As someone else pointed out, the actual leeway for arriving at a calculated resonant frequency that falls within the acceptable range of 7 to 12Hz is quite wide, referring to the (probably inaccurate) numbers that you finally decide to plug in to the equation. Which is why I say, "Just do it". Unless there is a huge and obvious disconnect between compliance and EM, you’ll be OK.

so for the actual mass of my arm to do all those calculationsת i need to add to the official spec of the manufacturer the weight of the screws and the lifter.
the headshell in my case ( well tempered) is part of the arm so i assume i was already taken into account.
i admit that i'll need to read yours explanation several times to completely understand it 😃
right now i am thinking about 3 carts, neither is Japanese.
Van den Hul DDT-II Special Moving Coil 
 Benz Micro Wood SL
E.A.T. JO N°5 CARTRIDGE.
the last one weight 15 g, while the first two are lighter, VDH 8.2 g, and benz micro *9 g.
so that was my major reason for asking that question .
also the EAT has COMPLIANCE, DYNAMIC/LATERAL           12 μm/mN
wile the VDH states- 

Compliance  15 without specifying which kind of value is it
so i'm confused with all that different values. 

I've used carts with 12-16g mass (16+ grams for Benz LPS) on my 9.5g EM Clearaudio tracer arm.  I just had to use the additional counterweight.  It sounded great, tracked well, and the resonance frequency as measured by the HiFi News test record was a hair over 7hz.  A bit low but turned out fine.

um = micron = one millionth of a meter.

if that was the question.

You can practice on the calculation chart that @yugiboy has posted.

With a well tempered you have variable damping to play with too, the raw resonance calculated for an undamped arm using the common formula won’t be the whole story.

http:// korfaudio.com/blog70

ok thanks everyone, i'll try to do my homework.
  

@stone1 , If you stick with arms on the lighter side, effective mass around 14 you can always add mass to tune the system. There are test records like the HI FI News Analog Test Record that have vertical and lateral resonance tracks that will give you a very good idea where you are. Then you add head shell weights until you get the lateral resonance down to 8 Hz or so. I like below 10 Hz as in my experience the bass is better. The published specs can only give you a ballpark idea of where you will be. There is enough variability to make accurate measurement of the pairing a much better approach. 

mijostyn
from my experience adding weight to the arm always harm somehow the sound 

You want to look at dynamic compliance @ 10 hz, that is the measurement that matters. Some cartridges only rate the cartridge at the 100 hz value. Generally you multiply the compliance numbers @ 100 hz by about 1.5x  to find the 10 hz compliance numbers. When looking at the resonance calculators, be certain to add in another 1 to 2 grams for the weight of the fasteners. As someone else mentioned, as long as you are able to balance the arm, free float, with the existing counter weight, then you should be fine. Otherwise, you will need a heavier counter weight. Below 11 grams is considered a low mass arm. 

thanks

Shucks. Ah jest tapes a penny to the top of the headshell and calls it good. (Oh wait, it's no longer April 1st, is it?)

This is my last attempt to advise, Just do it.

lewm
i of course appreciate your advice , and will use it after i'll decide wich cart i prefer

I went down this rabbit hole of concern when I had to buy a new turntable.  I wanted to use my very light Soundsmith SSMC1 B&O cartridge on a table with a much heavier arm than the B&O table.  I bought the table before I realized this might be an issue.  I never got an answer from forums to my question of, compliance charts notwithstanding, what I might actually hear with a bad compliance match.  I talked to Soundsmith and went for it, using their nylon screws to keep arm weight down.  They advised, assuming the counterweight had enough travel, azimuth and anti-skate would be most important.  I almost ran out of adjustment on the anti-skate, but It sounds fantastic.  I haven’t noticed any resonances if they are there.

Cartridge weight is included with arm mass in compliance calculations

Addendum: If you are really interested in performance, you will find that armtube and shell stiffness (young's modulus) greatly outweighs everything else.  Look up your armtube materials.  You might  then want to make your own armtube.  It depends on how high-end you are.  Don't be distracted by less important parameters.