Koetsu compliance compatibility issues

Just to update, I'm enjoying greatly my Koetsu with my older phantom arm. Loving the musical combo!

I'm using a koetsu jade with a VPI JMW-10 on a TNT turntable.
On paper the JMW-10 is a poor match for the jade as it's a unipivot with effective mass is in the 10-11gm range. That being said it sounds awfully good to me. Would an arm with a higher effective mass sound better? Maybe and one day I plan on finding out but for now the combo sounds great regardless of the math formulas.
A few things to consider, the stone body koetsu by being heavier by around 4gms then their wood/urushi counterparts and thus increase the effective mass of the arm their used with.
The effective mass of an arm can be increased by adding a cartridge weight. I know that VPI sells a 3gm aluminum weight for this purpose and I've seen a 5gm brass head shell weighs available.
Additionally by using a LIGHTER counterweight further back on the arm as opposed to a heavier counterweight closer to the pivot point will also increase the effective mass.
Just my 2 cents.

Hi franks,

Additionally by using a LIGHTER counterweight further back on the arm as opposed to a heavier counterweight closer to the pivot point will also increase the effective mass.

This statement does not make sense.

The physics formula for levers is M=FxD (M = moment (effectice mass), F = force , and D is distance from the pivot).

From my understanding, the moment (i.e. effective mass) is the upward force by the lever, the downward force of the mass post fulcrum is dependent only on the mass of the counterweight (and a constant gravitational constant!) and its product with its distance from the fulcrum.
Cheers<

Bobby

Well, this not an area of expertice but the effective mass is the moment of inertia and the further from the pivot point wheather the cartridge or counter weight increases the moment of inertia and hence the effective mass.
In your formula the F would appear to be the VTF thus the larger the D for any given VTF the higher the effective mass/moment of inertia.
There's a nice discussion of the topic by AJ Conti on the Basis website in the Vector tonearm section were he discusses changes in effective mass with using one or two counter weights and their relative positions on the arm.
Most importantly, happy listening and enjoy the music.

Hi Lewm,
"forget the formula but to try in a general way to match a low compliance cartridge with a medium to high mass tonearm, etc, etc."

well said. I definitely agree.

I suggest a 12" arm that helps trackability & makes a good match with heavy & low compliance cartridges. But a Koetsu is not the ordinary such cartridge and so the overall sound mix may becomes too relaxed & grand with the average 12' arm (think of SME, Ortofon, -but not DaVinci or Reed-).
It is a system depended situation. As always.
Anyway my system set-up does not benefit from the Sugano Onyx so, I can only express my limited experience.

George