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Herron VTPH-2 MC Loading Plugs

During this period of social distancing, I thought I would take the time and build a few loading resistors for my Herron phono stage. A couple of questions.
1) Do I merely solder a resistor between the center pin and ground of the rca plug?
2) If I want a 100 ohm load, do I simply purchase a 100 ohm resistor?
3) Other than the resistance value, what other resistor parameters should I look for? i.e. 5w, 10w , 1% tolerance etc
4) Will the type/manufacture/quality of resistor matter? Is the resistor in the signal path?

5) Does the quality of the rca plug matter?
6) Any other suggestion?
testpilot
almarg's avatar
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almarg
9,670 posts
 
1) Yes.

2) Yes.

3) 1% is probably a good idea, to keep the loading on the two channels matched. Also, the resistor doesn't have to be rated to handle significant power, and choosing one rated at 1/8 watt or even less would be fine. For example, if the cartridge puts out 0.5 mv a 100 ohm resistor would be dissipating (consuming) 0.0000000025 watts!

4a) I suspect so.
4b) Yes.

5) My guess is yes.

6) No. When I purchased my VTPH-2 I had Keith supply me with 1K plugs in addition to the 47K plugs he normally supplies. After performing some comparisons I ended up using no loading plugs. This is with an AT-ART9 cartridge.

Good luck. Regards,
-- Al


testpilot OP
932 posts
 
Thank you very much Al!
millercarbon's avatar
millercarbon
12,531 posts
 
Why not just call Keith? Have him send you some. Because all that stuff matters, and Keith has good plugs, resistors... and solder, which you didn't mention but matters. Also if you tell Keith your cartridge and taste in sound he can probably recommend a couple likely values to try.
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