Here is the HF sweep of a V15VMR
I like to keep an eye on the crosstalk level in the opposite channel... in many cases the resonance is far more obvious in the crosstalk than in the main f/r sweep!
This is the raw data without deducting the LCR
When I deduct the LCR I get this (sweep only this time, and the data was from a 96kHz rather than 192khz sweep... so missing the higher frequencies)
I am curious about the rise in crosstalk from around 15khz - I don't have a good explanation for it.
As expected there is a rise in x-talk coinciding with the primary resonance around 30k or just above. (I think the peak is at 32k...)
The expected ADC noise around 47k is there in both channels of course, but there is a rise in crosstalk preceding the sharp noise peak, indicating the noise peak may be very close to a secondary resonance at around 46k to 48k...
Things seem to go the hell around 60k - we may be reaching the upper physical limit of the stylus tracking ability. (test record run at 45rpm gives me a good signal out to 67kHx)
This implies a calculated "ETM" for the OEM VN5MR stylus of 0.23g if f=31k, and 0.21g if f=32k - from my measurements it appears that the specification quoted by Shure may have been slightly optimistic... it would take a primary resonance of 37k to get the ETM down to 0.17mg as quoted by Shure.
Caveat - this is measured on a well used example.... courtesy of Empirelvr (yes I am finally getting around to the OEM V15VMR part of the comparison...)
The LCR deducted sweep appears to show a secondary resonance at 37k - which would coincide with the Shure spec - but the higher resonance at around 31k seems to me to be the primary resonance...