COUNTERPOINT HYBRID PHONO STAGE UPGRADE


This is my first post, but I am well acquainted with this forum. I have recently imported a SA 5000 from a member and I am very impressed with the build quality, and performance of the line stage. It is a vast improvement over my modified SA 3. I have both service and owner's manuals, and the documentation is equally impressive, and worth the asking price.
I intend to do some of the Alta Vista upgrades, and would like to remove the JFET and inductor from the cathode circuit of the phono 1st gain stage as a starting point, and replace with a resistor, using the low gain common-cathode triode option for MM cartridge only.
I have no philosophical objection to hybrid circuitry, and I guess that Mike Elliot would have used the ARC SP11/15 as a reference for his own designs. Tube purists may have scoffed at the hybrid ARC products, but the people who make a living out of reviewing them, raved about it.
However, the Alta Vista upgrades for the SA 5000 and SA 9 involves removing the SS buffers and cathode JFETs, and associated circuitry. Any assistance in providing feedback and guidance on tackling these mods would be greatly appreciated.
Thanks in advance.


ozdiyer
I have 4- NOS Amperex 6922 gold pin 1972 made in Holland. I am going to fit Keystone micro- jacks on the jack board so I can swap resistors to get the right loading for the Decca cartridge. I also have schematic for the SA 5, that could be an option after I remove the JFET and upgrade the coupling caps to Dynamicaps. I don't use the phono all that much since I am getting incredible sound from digital after upgrading the CD player and DAC last year. I had a Koetsu red MC , but I prefer the Garrott- Decca Gold which is in a class of its own, but needs careful set up. 

the Amperex NOS tubes are a good choice. I am using 6 Siemens NOS  6922s and a Tele NOS 12AX7 in the power supply  spot  but that is my preference.
The SA5 schematic should help you. In a conversation with Mike Elliot he stated that the circuit in the SA5 AND SA5000 were pretty much the same except for the extra bells and whistles on the SA5000. Good luck with your changes / upgrades.