I looked over the specs of the Ortofon, and it should be an excellent match with both your EAR 834p and your VPI tonearm (I'm assuming its a JMW9.) The EAR in MC mode has enough gain for any cartridge (approx. 68db). The Ortofon is a heavy cartridge (13.0g), but it does track heavy too (2.3 - 2.8 grams) so it should be easy to dial in the VTF. Compliance is 16, which puts it in the desirable range of the JMW 9 arm.
Cheers.
Cheers.