Yesrogers;
I think the end stub on those arms are OK (RB 700?). What you are looking for is a metal end stub that is very secure on the arm, so that it is essentially one piece and I think that arm already has that. Find out which of those weights can be used on the existing stub (if it's OK, i.e.- metal and rigid). You can definitely get improved bass with a better end stub. Groovetracer subplatters are supposed to be excellent. They are well machined alloy subplatters, which should enhance the PRaT on that deck, but again look at what you already have. The marbles sound like a good idea. They're cheap and reversible, if you don't like it. I use pumice sponges under my Rega feet and they really opened up the soundstage. Rega's are very sensitive to the base material/shelf they are sitting on, so check that out. They(like their design)need a light and rigid platform to sit on. A wall mounted shelf is best, otherwise a light floor standing rack works well too. Check out Ken Lyon's posts on "vinyl asylum". He's been tweaking these decks for years and seems to have squeezed every last drop of PRaT out of them. Even stock, they are a ton of fun to listen to when they are set up correctly.
I think the end stub on those arms are OK (RB 700?). What you are looking for is a metal end stub that is very secure on the arm, so that it is essentially one piece and I think that arm already has that. Find out which of those weights can be used on the existing stub (if it's OK, i.e.- metal and rigid). You can definitely get improved bass with a better end stub. Groovetracer subplatters are supposed to be excellent. They are well machined alloy subplatters, which should enhance the PRaT on that deck, but again look at what you already have. The marbles sound like a good idea. They're cheap and reversible, if you don't like it. I use pumice sponges under my Rega feet and they really opened up the soundstage. Rega's are very sensitive to the base material/shelf they are sitting on, so check that out. They(like their design)need a light and rigid platform to sit on. A wall mounted shelf is best, otherwise a light floor standing rack works well too. Check out Ken Lyon's posts on "vinyl asylum". He's been tweaking these decks for years and seems to have squeezed every last drop of PRaT out of them. Even stock, they are a ton of fun to listen to when they are set up correctly.