Fidelity Research FR-64x

@nandric 

(Slightly off topic)

One should use the weight which can be moved nearest to the pivot. The least inertia is the result.

Is this actually true? As long as what you're balancing doesn't change (i.e., the cartridge & headshell stay the same), doesn't the force on the counterweight side also have to stay the same? So if you use a heavier weight and get it closer, the end result is the same as using a lighter weight further out. In other words, inertia is the product of distance & mass, but you're changing both in order to balance the same thing on the other side.

As indicated by others, $150 for FR64fx is a steal. For these older tonearms and other older products, silver is probably better. For current products, I products I prefer high-quality copper.

@mulveling 

I currently have a Graham Phantom Supreme 10" ($6.7K new) and Clearaudio Universal 12" ($6.5K new) mounted; I expect this FR64fx should easily compete with (if not beat) them.

I really like my FR64fx, but is it really comparable to >$6.5k tonearms? I'm interested in your findings.

@nandric Sorry! I meant @chakster. He acquired an FR64fx to use with his FR7 & SPU.

And regarding the mechanics, since you are adjusting both the distance and the mass so that they balance exactly the same thing on the other side, it's not obvious to me why anything important would really be different. If you're moving the same mass to be closer, then you are clearly having an effect, but then you would also need to adjust the mass on the cartridge side to remain in balance. But I'd be happy to be educated on this.

@invictus005

IMO, silver is actually better when it comes to tonearm wire because of the low fragile cartridge signal. 

Good copper has lower resistance than silver:
https://pubs.acs.org/doi/abs/10.1021/cg1003808

Anyone paying $1000-$2000 for an FR64 variant, should really stop and think about what they're doing. For that price one can get a brand new SME 309 or a used SME V.

I'm not making a claim about the relative quality of the tonearms in question, but neither of those SME models would actually be able to use the FR7 or SPU cartridges that for instance @nandric is intending to use with his FR64fx.

@dover 
Since the torque created by the mass of the cartridge that you're trying to balance is force x distance, a larger counterweight closer to the pivot can have the same torque but lower moment of inertia. Ok. Thanks.

@chakster Good to hear you're enjoying it. Have you tried other cartridges? How do you like it compared to other tonearms?