100 to 400 pf is an unusually wide range for recommended loading of a moving magnet cartridge. My suspicion is that the tonal balance of the cartridge will vary significantly within that range.
As a rough guess, the capacitance of the 46 inch phono cable plus the 120 pf input capacitance of the phono stage plus the capacitance of the turntable's internal wiring and connectors is perhaps a bit more than 300 pf.
The lowest capacitance low cost decent quality cable I am aware of is Blue Jeans LC-1, at about 12 pf/foot, and $27.75 for a 1.5 foot stereo pair. Using that cable in that length would probably cut the total load capacitance almost in half, and would be a worthwhile experiment IMO. Even if it didn't solve the problem, having that cable would expand your options in the future if you ultimately decide to go to a different cartridge.
I am assuming, btw, that the connectors on the rear of the turntable are RCAs, as appears to be the case based on the illustration in the manual.
That cable, like most RCA cables that are available these days, does not include a separate ground wire. You could either use the ground wire of the existing cable for that purpose, while leaving the RCAs of the existing cable unconnected, or else use some plain old 18 or 20 gauge hookup wire, which is readily available at Radio Shack and elsewhere.
If you ultimately find yourself wanting to experiment with higher load capacitances, consider spending $49 on this kit, listed as part number DBP-6 here.
It's certainly possible that doing these things won't fully or even mostly resolve the issue, but even if that proves to be the case doing these experiments will minimize the likelihood that you end up compensating for one inaccuracy by introducing or increasing another one, which is usually not the best way to go.
Regards,
-- Al
As a rough guess, the capacitance of the 46 inch phono cable plus the 120 pf input capacitance of the phono stage plus the capacitance of the turntable's internal wiring and connectors is perhaps a bit more than 300 pf.
The lowest capacitance low cost decent quality cable I am aware of is Blue Jeans LC-1, at about 12 pf/foot, and $27.75 for a 1.5 foot stereo pair. Using that cable in that length would probably cut the total load capacitance almost in half, and would be a worthwhile experiment IMO. Even if it didn't solve the problem, having that cable would expand your options in the future if you ultimately decide to go to a different cartridge.
I am assuming, btw, that the connectors on the rear of the turntable are RCAs, as appears to be the case based on the illustration in the manual.
That cable, like most RCA cables that are available these days, does not include a separate ground wire. You could either use the ground wire of the existing cable for that purpose, while leaving the RCAs of the existing cable unconnected, or else use some plain old 18 or 20 gauge hookup wire, which is readily available at Radio Shack and elsewhere.
If you ultimately find yourself wanting to experiment with higher load capacitances, consider spending $49 on this kit, listed as part number DBP-6 here.
It's certainly possible that doing these things won't fully or even mostly resolve the issue, but even if that proves to be the case doing these experiments will minimize the likelihood that you end up compensating for one inaccuracy by introducing or increasing another one, which is usually not the best way to go.
Regards,
-- Al