Recommended cartridge weight for VPI Scoutmaster

Would it be unwise to use a cartridge weighing 6 grams on the JMW-9 tonearm of the VPI Scoutmaster? I think the recommended cartidge weight for the JMW-9 tonearm is 9-12 grams. Thanks
You should check the VPI web site, I found the following in the "What's new" section. "Available for better compatibility with the light low compliance cartridges being made today are 3 gram stainless steel cartridge weights. Cost is $15.00 retail"
What's fascinating is that VPI had to know years ago with complaint after complaint that the JMW-9 needs more headshell weight and has a poorly designed anti-skating mechanism to finally address this now with cheap 3 gram weights at the customer's expense!!!
This is a flawed design with patchworked remedies IMO.
i don't think that is the case at all, actually there are very few carts. out there, that are so light, that they would require a headshell weight, the Dyna. 17d2 being one of them, i use the 17d on my scoutmaster with the headshell weight (which vpi sent me free of charge btw) and it works very well. anyway, just wanted to throw my opnion out there.
I use the grado ref sonata with the free weight vpi
sent me with great success
I had to pay for my weight. You'll need one if using the Clearaudio Wood Virtuoso to get the 2 gram recommended tracking force. At the same time though they did send me a replacement washer for my center spindle for free.

Since you asked a theoretical question you may have been seeking a theoretical answer without regard to specific cartridges. (That's my excuse for this post and I'm stickin' to it!)

It depends on the compliance of the cartridge. If VPI is recommending cartridges based only on mass, without regard to compliance, they are providing incomplete information that will lead to unpredictable results.

Every cartridge/tonearm combination has a "resonance frequency" (or frequencies) which, if encountered, will send the system into mechanical feedback-enhanced oscillation. Picture a car with bad shocks going over a big bump. The car continues to bounce up and down on its springs long after passing the bump. Now imagine the same car going over a regular series of such bumps. Given adequate acceleration, the car would actually launch itself into mid-air. Bam!

Now imagine the road is made of vinyl and the car's tires are made of sharpened diamonds... :-(

Resonance frequencies cannot be eliminated, but they can be predicted. Therefore, the best we can do is choose components whose resonance frequency is unlikely to be encountered in real world playback. This is the first goal of cartridge/tonearm mass-matching.

Resonance frequencies between 8-12Hz are widely considered safest. Anything higher starts to approach the LF information on some records. Anything lower starts to approach the natural frequency of record warps, footfalls, building movements, etc.

To estimate the resonance frequency of any particular cartridge and tonearm, one needs three data points:

- effective mass of the tonearm
- mass of the cartridge
- compliance of the cartridge

Theoretical statements about cartridge/arm compatibility based on only two of these data points are meaningless.