To damp or not to damp JMW-9 Sig ?


Just got this tonearm for my ScoutMaster. A great addition I might add. I haven't experimented with the damping yet. This will come. But I was wondering what differences I might hear with it damped? I'm using a DV 20XL cartridge. Thanks
128x128artemus_5
I'm a long term TNT/JMW-10 owner. The issue of damping is very cartridge dependent. In general the high compliance catridges like the benz and the grado's benefit from some damping. Low compliance cartridges do not. When I had a grado reference I had the damping trough about half full. After I upgraded to a koetsu jade, a low compliance cartridge, I use no damping. The dynevector is a low side of medium compliance cartridge thus it may or may not benefit from a small amount of damping. You might want to try just a few drops of the damping fluid in the trough and compare it with no damping.
12-31-07: Artemus_5
FTR, I thought about trying less fluid. I thought it may have been over filled. But there was no fluid on the underside of the JMW-9 arm when I took it off of the pivot. That made me believe that there was not too much fluid. The trough was about 1/2 full.

I suppose that if there is no fluid on the underside of the arm - the part of the bearing in the arm wand -, then there has been no damping going on at all. I had the same experience. I'd say everyone who fills the well 1/3 or 1/2 should check out if there is any fluid on the bearing on the arm wand. If I have understood HW right, you increase/decrease damping with the screw on top of the arm wand.

Best
Please be more specific about the adjusting screw for damping. I find no mention of it in the instruction manual, and don't see one one my arm, although mine in a 10.5i which very well may be different
On top of the bearing on the arm tube (when you look at the arm from above) there is a hole with a screw in it. This screw will lower or raise the top of the bearing inside.

No metion in the manual, that is right, but this is what I've been told by HW at VPI.

"The center screw in the top of the armwand adjusts the damping level. Clockwise from the top and you have less, counterclockwise and you have more. Don't drop it too low as you need clearance for motion."
Parelius, I just looked at the arm and I see the hole you are talking about, but I cannot see a screw inside. Now this may be due to poor eyesight, but I tried the two hex keys which came with the table and neither fit anything inside the hole. What type of tool is used to turn the screw?