SME V and cartridge spacer

Sorry, I also would need the cu (compliance unit) of course, the arm mass for the SME V I'd use as 10.5 gram.
However, if you use the silicone damping tray function (some more or less) it can be argued that it would effect the arm mass slightly too. By this shifting the arm mass toward the quoted upper range of 10—11 gram e.g. 11 gram, this if the pin is screwed down to the second marking for example.
In other words pretty much fully immersed in the silicone. 
This is all very finicky and in final analysis it'd STILL depend on your listening impression what you prefer of course. 
In my experience, a low cartridge weight ~ 6 gram and high/soft compliance > 20 cu, asking for a light mass arm, I would use no damping at all, lifting the screw pin up past the first marking (tray filled to the correct level with the correct viscosity silicone gue). 
On the other hand, with a cu of about 15-16 (medium stiff) and a cartridge mass of ~9 grams I find a medium immersion somewhere between the two markings suitable, and as the cartridge mass goes up to e.g. 13 grams (still at 15-16 cu) the damping again can be reduced toward no damping, since the increased cartridge mass is adding more inertia (this is my rational). 
A low cu of 10 and less, with a low cartridge mass, e.g. a 103 Dennon with plastic body, would then again require a higher damping setting, assuming my rational makes any sense 😉
Yet, trust your ears! 
Michélle 

Ok, actually did find the Purple Heart specs on line:
Weight: 7 g (jolly light for its size methinks) 
Compliance : 16cu 
Arm mass used: 10.5 g
Therefore resonance frequency: 8,7793 Hz
This being well within 7 - 12 Hz range. 

As for the damping, I'd suggest pretty much in the middle between the two ring markings and more towards the bottom ring mark (lighter damping).
This when I compare it to my Ortofon Quintet Black, with Shibata stylus, 10.8 g mass incl. cart leads, brass mounting screws, and cu 15. Resulting in rf of 8.9 Hz. 
Michélle 

So, justmetoo, by your calculations what would adding the 3 additional grams for the spacer do to the resonance frequency, everything else being the same?

Also, could someone explain what one might hear in ones system, all else being the same, with the cartridge/arm resonance frequency at either ends of the acceptable range, say 7-8 and 11-12Hz?

The rf without the spacer by using the 7 gram cart mass only, is showing up as 9.5 Hz.
Still well within the accepted range of 7-12 Hz. 
Though in this case I'm not quite sure about the best damping setting with the SME V arm. 

My intuition tells me the set-up with the spacer, considering the cu of 16, will be more favourable.
If the cu was more toward 18-20 then I'd opt for the setting without spacer, but not with the SME V arm, due to the issues mentioned. 
So all this looks IMO (and YMMV), just fine  using the spacer with this cartridge, on the SME V arm.
Finally, DO NOT underestimate the finer differences in SQ that small changes in damping settings will do. 
Michélle