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AR PH3-SE with Benz Micro Ruby 2

I just recently purchased a used AR PH3-SE phono pre-amp and Benz Micro Ruby 2 cartridge.

Has anyone had any experience with the two together and if so, did they perform well? I know the output of the Ruby is pretty low at .3mV and hope this won't be an issue.

I am also concerned about the impedence loading on the PH3-SE which is adjustable. Should I leave it at the factory 47kOhm or try another setting?

Anyone with comments?
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Showing 1 response by marakanetz

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marakanetz
5,473 posts
 
PH3 minimal requirement is .5mV output if used with active preamp and .9mV can be used with passive.

47k is not the best setting for Ruby but first you should break-in ruby for at least 50 hours before experimenting with impedance settings.

I used RS potentiometers connected to the terminals and Ohmmeter connected there as well to measure the result resistance. I used two mono ones to carefully adjust one channel to another and than make sure that measured resistance is equal.

Than I calculated the value of the resistor by the following equation for the resistors connected in parallel:

Rm = 47k*Rv/47k+Rv

where Rm is measured resistance and Rv is the "G-point" value that needs to be calculated.

I set for Lyra Helikon the value of 127 Ohms resistor that in result creates a load of approximately 114 Ohms.

Please note that if Rv approaches to 1 or in math terms and/or symbols
Rv->1
than overall load resistance will also approach 1 another words that if Rm is relatively small to 47K (30Ohm for instance) than Rv value will approach Rm or in the math terms and/or symbols
Rv->Rm
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