Seeking arm suggestions for a Grace F9R

Robbie, Did you actually measure a resonant frequency of 7 Hz, or did you calculate it based on assumptions of compliance and effective mass?  If the latter, and especially if you're really not having an audible problem with bass reproduction, I would say forgeddaboudit.  This business of worrying about resonant frequency is one of the most over-rated in vinyl world. FWIW, I run my Grace Ruby re-tipped by SS in a Dynavector DV505 with original DV headshell.  Like Dave says, it's a great cartridge.

Glad I checked in, sooner than my usual once a week. Silly me, to have trusted the Grace compliance figures, on the Vinyl Engine site. I’ve no doubt, their own manuals, would be the authority. VE doesn’t mention at what frequency their figures are given, nor- was I thinking about Japanese spec(Oldtimers Disease). And, like I said, I couldn’t swear to anything, regarding Mr Ledermann’s options, methods, materials, or end compliances, with his Grace rebuilds(in my reply to Mr chakster), so- thanks for that info, Mr dgarretson. I guess, now I can(except for whether the compliance is higher or lower). Happy listening, everyone! https://www.vinylengine.com/cartridge_database.php?m=Grace&t=any&mod=&sort=2&Search=...=

Thanks for all the responses everyone.  To answer all your questions: I'll look into the Magnepan Untrac rodman, thanks for the suggestion.  Yogiboy, I am using as light a headshell as I have at just under 7 gr., the stock Lustre is 11gr. I bought an 8 gr. ADC like no-brand magnesium one and 220 sanded just over a gr. off of it's top. I thankfully don't have any warped records so that hasn't been an issue.  I've also set the arms VTF dial at zero and used just the counterweight to apply the VTF hoping to reduce a little more arm mass. Dgareetson is correct, the Soundsmith ruby stylus I have is their production product, not a re-tip or re-build of an original Grace. I have the VTF set at 1.3 gr as called for on it's box, not 1.8 gr. as you suggested.  Should I try increasing it a half gram?  Do you think the F9 would mate well with an EPA-100?  I'll give the Micro Seiki's another look also.  Lewn, I determined the resonance figure by watching 2 test record sweeps, so it's hard to be more specific than "in the 7's", but I'd say more low to mid 7's.  It's stand is on a poured slab floor so I don't have footfalls in this range to worry about. So you think in changing arms trying to get to the desired 10 hz resonance I could be chasing specs rather than really achieving better sound?  I don't think I have 'golden ears' but to me it's sounding quite nice with only about 25-30 hours so far. 

The range of acceptable resonant frequency is generally taken to be 8 to 12 Hz, not 10 Hz on the nose.  We'd be going even more nuts, if we sought an exact 10 Hz.  At 7 Hz, I repeat, do you have a perceptible problem? Speaking of footfalls, if you know anyone who tap dances at 7 Hz (that's "cycles per second"), he ought to be in a Broadway show.  The only way you'll hear an improvement, if you change tonearms to achieve 10Hz (or the acceptable range of 8 to 12 Hz), is if the new tonearm is simply superior to what you are using now.  

So, if you are estimating RF with a test LP, then you have an equation with two unknowns (Compliance and Effective Mass, but maybe not, if SS gave you a figure for compliance).  Assuming C and M are not exactly known, how are you going to calculate exactly what Effective Mass will move the RF up to 10 Hz?  Like I said, it ain't worth the trouble.  Also, because RF is inversely proportional to the square root of the product of C times M, it may require a very light tonearm to move RF from 7 to 10 Hz.  It's "LewM", by the way.