Sayas, this is what the Lyra webpage says about the Helikon:
The cantilever compliance has been tuned to 12cu which is a comfortable level for most tone-arms (typically medium mass) available on the market today. Compliance is a measure of the cartridge suspension's stiffness. A stiffer suspension requires a higher mass tone-arm, while a looser suspension (high compliance) require a low-mass tone-arm. The Lyra Helikon can be used in any high-performance, rigid bearing, resonance-free, medium mass radial or linear-tracking type tone-arm with integrated head-shell and adjustable anti-skating force.
I could not find the effective mass data on the JMW 10.5, but I did go the the VPI website. It is a unipivot design, with no anti-skate provisions. It says it doesn't need one.
Now, if you notice, the Lyra specs call for a "rigid bearing" tonearm with "adjustable anti-skating force". The mass of the JMW may or may not be correct(couldn't find data), but the other parameters are not in keeping with the Lyra factory recommendations for the Helikon, or other Lyra carts. This may not preclude use of this cart in the JMW arms, but it is an indicator of mismatch. My experience with lower compliance moving coils, is that they do not match well with unipivots. The rating of the Helikon, at 12cu, is not really low compliance, and leans toward medium. It may be borderline. My advise is based on my experience with slightly(and greatly) lower compliance carts with unipivots. These carts tend to "wag" a unipivot arm around, even if they have fluid damping, or outriggers. The lack of bearings in the horizontal plane allows the cartridge to "rock the baby" and change azimuth angle during play. This is not a problem with the higher compliance cartridges. Also, alot of unipivots are light arms which is also a mismatch with low compliance carts. So, I haven't tried this cartridge with this arm, but the indicators show strong warning signs. I cannot make a recommendation of a combination like that. This is not an indictment of the JMW arms, just that it makes certain types of cartridges better matches for it, than others. The JMW arms are wonderful arms in the right application. I just don't think that the Lyra is the right application, although it may work. I don't like to make borderline recommendations to others. I may try them out myself, at my own risk, but shy away from experimenting with other people's money. I hope this answers your question.
I see from your "virtual system" that you have a TNT and a Helikon. It doesn't say if you have a JMW arm. Do you? If so, maybe you can share some of your experience with us on the viability of the Lyra carts in the JMW. I personally think the Lyra carts are great.
