You can try fixing the tonearm weight problem two ways. First, I'm assuming that you're adjusting the counterweight and rebalancing tonearm after you installed the new cart, right? You'll have to re-zero the gram setting to compensate for the new heavier cart. If you didn't do that, then re-read how you do that with your table. If you did do that, then your problem is that your counterweight isn't heavy enough, or can't get enough leverage to compensate for your heavy cart. You can try a couple of things. You can try taping that 4g weight to your counterweight and see if that helps. You can also usually adjust the leverage that the needle itself has. I looked at a pic of your carts and it looks like there are a pair of screws on the top of the cart. Loosen these screws and slide the headshell all the way back. This will help lighten the load a little bit more by reducing the leverage the cart has on the counterweight.

Your skipping problem sounds like you need to adjust the anti-skate control. "I have no idea how to play with the turntable's settings" I agree You really need to read your users manual and learn how to set the tonearm weight and the anti-skate adjustment. This should solve your problems.

As far as the balance being off in one of your needles, make sure that your weights and anti-skate is set correctly first, then if it is still happening, double check all of your connections, including making sure that the needle is plugged all the way into your headshell. If that doesn't work, then try switching channels on your mixer, try switching the needles on your TT, switch out the two new ones with eachother then with the old ones and determine if the problem is with your needle, your connection, your mixer etc.

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When you dance, the DJ takes you on a journey, but he or she is usually not the focus of your experience at a club or festival or wherever you hear the music. Dancing is. Music is.