Thanks very much, Bill. I’ll definitely keep your suggestion in mind. And thanks also for your long-standing advocacy of the VTPH-2, which significantly contributed to my decision to purchase it a few months ago. In addition to its great sonics, btw, I am continually amazed at how absolutely quiet it is.
Lew, I’ve never seen a load capacitance recommendation for the F-9E Ruby. FWIW, though, as you’ve probably seen the datasheet for the original non-Ruby version, while not explicitly stating a recommended load capacitance, indicates that the specified 45 kHz bandwidth (necessary for reproduction of some quadraphonic formats) is based on "operating conditions" of 80 pf in parallel with 100K. (Although elsewhere in the datasheet resistive loading of 47K is indicated).
Regarding the impedance of the Herron’s LOMC input, yes I too would expect that some resistance would be incorporated between the gate of the FET and ground. But even if that is so, based on the following statement in the VTPH-2’s description I’d imagine that it would be in the millions of ohms, which in the context of cartridge loading is essentially infinite:
Best regards,
--Al
Lew, I’ve never seen a load capacitance recommendation for the F-9E Ruby. FWIW, though, as you’ve probably seen the datasheet for the original non-Ruby version, while not explicitly stating a recommended load capacitance, indicates that the specified 45 kHz bandwidth (necessary for reproduction of some quadraphonic formats) is based on "operating conditions" of 80 pf in parallel with 100K. (Although elsewhere in the datasheet resistive loading of 47K is indicated).
Regarding the impedance of the Herron’s LOMC input, yes I too would expect that some resistance would be incorporated between the gate of the FET and ground. But even if that is so, based on the following statement in the VTPH-2’s description I’d imagine that it would be in the millions of ohms, which in the context of cartridge loading is essentially infinite:
The VTPH-2 will not load the cartridge at all if no loading resistors are plugged into the MC loading inputs. This is because the moving coil input stage of the VTPH-2 utilizes the electric field generated by the cartridge to amplify the voltage and no current is drawn from the cartridge (there is no load on the cartridge). This can give an extended sense of dynamic freedom and sound stage as it reduces the work done by the cartridge and cartridge/groove interaction. Note B: Some cartridges will need loading in order to reduce their inherent rise in high frequency response....Regarding Soundsmith’s CL vs. OCL, one of the main reasons I chose the CL (in addition to favorable commentary here some years ago by very knowledgeable members such as Mofimadness) was that I had some concern that with the OCL version SRA/VTA might be more critical than I would prefer to deal with (even though the Unitrac arm provides on-the-fly SRA/VTA adjustment). That concern being raised in my mind by the fact that the OCL is described as having a "diamond shape [that] closely resembles the actual cutting stylus that is used to create the master record."
... We recommend trying the VTPH-2 in the no-load configuration as the unit is supplied for most moving coil cartridges. 47,000 (47k) ohm RCA load plugs are supplied with the unit for optional use. Additional user specified loading plugs can also be purchased with the unit.
Best regards,
--Al