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RB300 tweaking problem

I have an RB300 mounted on a Townshend Rock Mk. III. This turntable incorporates a damping trough at the cartridge. To use this trough, a outrigger assembly is mounted at the headshell. The RB300 came from Townshend. It came with the tungsten CW w/ an additional weight epoxied to it to offset the added mass of the outrigger. The diameter of the hole on the additional weight is larger than the shaft. Its weight is being supported by the tungsten cw.

I am using the latest Shelter 501.

I thought I would try one of the cw upgrades. I went with the Mitchell. The problem that I am having is that in order to load the cartridge at 1.8 grams, the center of the main weight is a full 2" behind the pivot.

Any suggestions here? Should I add more mass to the Mitchell? If so, how?

Thanks for any help.
smctigue
plato
1,543 posts
 
Hmmm, that's weird. I had a Rock Mk-3 with the Rega RB300 and as I recall the stock outrigger assembly was very light in weight. Has someone made a home-made outrigger that weighs a lot more, by any chance? If so, perhaps you could order or find the original assembly. And if not, I'm sure it wouldn't be that difficult to make one. Any machinist could do this easily... I never had a problem balancing the arm and I don't think I needed the extra weight.
smctigue OP
9 posts
 
It's the stock assembly. I am the original owner.
brusson's avatar
brusson
9 posts
 
Don't use the spring to set tracking force; use the counterweight(s)and a separate tracking force gauge. That should move them closer to the pivot point.
tafka_steve
115 posts
 
You can move the weight closer to the pivot if you have an external tracking force gauge. Set the Rega spring gauge tracking force to zero, then move the counterweight to apply the tracking force measured on an external gauge. The disadvantage of this method is that the Rega spring is actually at its maximum tension to maximize upward force at the 0 gram setting, and this may color the sound.
smctigue OP
9 posts
 
The tracking force is set at 3.5. According to the Mitchell literature, doing so deactivates the spring.
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