Koetsu compliance compatibility issues


hi guys,

am wondering, what arms are you guys using w/ the koetsu carts.
For example, a black has compliance of 5 only and weight is 9 grams.
If i use an arm of 14 grams, its resonance frequency is 15 hz which is the upper limit of being acceptable.
Nonetheless, would like to hear inputs on real world situations on what arms you guys are using with koetsu & despite of the high resonance frequency on most common arms, how the sound is ?
Thanks for the inputs.
nolitan
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
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 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
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.
Just to update, I'm enjoying greatly my Koetsu with my older phantom arm. Loving the musical combo!
Geoch, You wrote, "So, don't bother. You simply can't trick the formula."
But in fact the formula itself is "tricky" and only gives you a ballpark estimate of the resonant frequency, even if your input data are accurate with respect to one's particular sample of a particular cartridge. So my approach would be to 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.

I am one who does use ESLs and OTLs and who does very much like the Urushi that I own. I also have a Colibri and an Ortofon MC7500 and several tonearms and turntables. Many days, I prefer the Urushi over all. I don't think a 12" arm is necessary to enjoy the Urushi, but when I finally acquire one, I will try it.
No one is likely to have the breadth of experience described by Syntax. However, my Koetsu Urushi, which seems to be at least a bit higher in compliance than your Black, ran well in my Triplanar (effective mass = 11 gm) but is even better in the Kenwood L07D tonearm, with the stock 12-gm headshell. I could believe it would benefit from a higher effective mass tonearm like the FRs.
The Onyx (Sugano) was a complete disaster with my Pluto 9A.
In contrast, this arm matches almost well with the Goldfinger (similar mass/different compliance). It seems its a matter of compliance more than cartridge's mass. But this is a contradiction as later, after mounting the Denon DL103 (even less compliance than Onyx) the results were also unacceptable , but better than Onyx due to the lighter Denon body.
What was really happened ?
The Goldfinger has a phenomenal trackability especially in contrast with the Onyx.
This alone was enough for me to stop trying to find a proper arm for Koetsu.
Of course those are examples of extemely wrong matching (uknown Pluto effective mass) & if you dare to test for trackability, you may aware that you have a damaged Koetsu sample.
Now with the Colibri (less than half the weight of both & 35 Cu compliance) my Pluto makes the perfect pair.
So, don't bother. You simply can't trick the formula.
The Alphason HR100 is a great arm for Denon DL304, so maybe matches equally well with Koetsu Black.
If you really like the unique Koetsu sound, you must first purchase a robust & preferably 12" arm. Then, pair them with an electrostatic speaker & some OTL power amps.
Somehow I feel that letting your Koetsu decide for your system building, maybe is a little too much love for her.
Sorry for I can't help a lot, but I value Koetsus even less than DL304 and way below the DLS1. They have much character to enjoy, but the trade-offs are many more.
Having said that,I admit that If I would like electrostatics (over horns) & OTL (over SET), I definitely give a chance to Koetsu.
It has a beauty unable to find elsewhere in the chain.

George
Nolitan,

I have had not problems between the Koetsu & the B44 or my Lyra for that matter. Tracking is very very good and with the Magneglide it is simple to make adjustments for the left & right groove walls if older records seem a little off. And it is repeatable. VTA is also a snap and repeatable if you want to make changes between 120,140,180 & 200 gram vinyl. This arm has been a joy over the arms I have hade in the past. I will upgrade to the II asap and if cash is available.
I agree with Syntax. The FR tone arms are the best I have heard with them
in particular their stonebody cartridges.
I tried Koetsus with Airline, Triplanar, Phantom, DaVinci and FR-64s. From those I preferred FR-64s (and 66s).
thanks for the inputs Hevac- do you have any issues with tracking, etc on the phanton/koetsu combo ?
Thats good to know.
I am using a Koetsu Urushi/Graham Phantom on a Basis Debut with no problems at all. It sounds gggggreat.
my friend overseas chimed on, regards this matter. He feels that the Koetsu are best with gimballed arms in the likes of SME and Triplanar. Anyone feels othewise so ?
Alphason 1000s and a Koetsu Onyx. Couldn't be happier with the sound. Tough to find an Alphason these days, yet the fun is in the hunt considering the price/value. This titanium arm was built with a Koetsu in mind. My friend has an SME 20 with an SME V arm/black and it sounds interesting eminating from those quads.
I am using an Onyx with an Ortofon 309D. The charts say there is a compliance mismatch. It still sounds pretty marvelous to me. I am not sure cartridge/ arm compliance guidelines are anything more than guidance.
I bought a Basis 2500 TT/Vector 1 arm with a Rosewood cart. I replaced the cart with a Urushi and am very pleased with the combination/sound!!!