Anything between 8 - 15 Hz is ok, it is not necessary to have 8Hz resonance freq, more like 10-12Hz in theory.
The FR-64s and 64FX are two flagship models designed by Ikeda-San, both are perfect match for his flagship cartridges such as FR-7f and FR-7fz. The only difference is the optional W-250 counterweight for 64fx arm which is a must have for use with FR-7 series of cartridges.
There are long versions of both arms made.
I am using FR-7fz on my 64fx with W-250 counterweight and N-60 nut.
and i have not mounted yet my FR-64s with B-60 base and with IKEDA 9 III cartridge.
However, my current favorite is Miyabi cartridge by Takeda-San on Lustre GST-801 tonearm.
The FR-64s and 64FX are two flagship models designed by Ikeda-San, both are perfect match for his flagship cartridges such as FR-7f and FR-7fz. The only difference is the optional W-250 counterweight for 64fx arm which is a must have for use with FR-7 series of cartridges.
There are long versions of both arms made.
I am using FR-7fz on my 64fx with W-250 counterweight and N-60 nut.
and i have not mounted yet my FR-64s with B-60 base and with IKEDA 9 III cartridge.
However, my current favorite is Miyabi cartridge by Takeda-San on Lustre GST-801 tonearm.