Music Hall MMF-7 tonearm mass?

I want to try a different cartridge with my MMF-7 tonearm, but before I purchase a cartridge, I want to insure the proper tonearm / cartridge combination. I've checked the owners manual for the MMF-7, but I do not see the specification for the mass of the tonearm.
Does anyone know what the mass is for the Music Hall MMF-7 tonearm, so I can calculate the resonant frequency of the tonearm / cartridge combination?
Pro-Ject's technical specification sheet for the Pro-Ject 9 aluminum arm shows an effective mass of 11 grams. I've run a LOMC cartridge weighing 8.6 grams using the heavyweight 120 gram counterweight and it sounds great.