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VPI JMW 12.5 counterweight upgrade

Adjusting the azimuth on the VPI with the off-set counter weight is challenging: altering the azimuth often shifts the weight along the shaft and alters the VTA. I found a reasonably priced counter weight replacement that allows for relatively easy setting of VTA and azimuth, independently. I also discovered a sonic improvement over the VPI counter weight.

The product is manufactured and designed by an engineer in the UK. It seems that he designed his initial counter weight for the Hadcock tonearm and expanded to other unipivot arms. His product is on Ebay and is called the XTCW.
redglobe
brf
1,715 posts
 
Soundsmith's makes a very good alternative.
redglobe OP
223 posts
 
Dear BRF, I was aware of the Sound Smith's product before I purchased the XTCW. The difference is that the XTCW lowers the counter weight below the horizontal line of the cartridge, thereby, providing greater, potential, counter-force of those produced by the grooves acting on the stylus. The physics made sense and the improved sonics (musical reproduction) validated the science.

I suspect, also, that the resonant characteristics of the brass would help cancel out the resonant frequencies of the stainless steel. It sure sounds great, and maybe it does help cancel out some of the induced resonance.

So, the XTCW facilitated setup of VTA and azimuth, and it improved the music reproduction. Not bad for $80.
stringreen's avatar
stringreen
6,463 posts
 
The VPI arms now have a lowered counterweight as you describe.
redglobe OP
223 posts
 
Dear Stringreen,

I had VPI's drop-style counter weight, as mentioned in my original thread. The XTCW has a much lower center of gravity. It provides greater stability and sonic performance than the VPI counter weight.
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