MM cart. Recommendation

I'd stick to a MM with that arm. And a light one. I understand that the Grado Reference Sonata sounds very good with the Sonus and you might be able to find one used for that or a bit more if patient. The Grado NEEDS a light arm to show its skills. The Shure is also an option, but I'd wager the Grado might best it on that particular arm.

BTW, what are you using for spindle to pivot distance - 225mm as per the literature or 211-212 like the original Mayware (on which it is based)? I ask because while the Sonus lit says the effective length is 240mm, I measure mine to be 229. You?

Guess it's time for more research based on these suggestions. 4yanx - I measure about 226mm from the edge of the spindle or 230mm from the center. That puts the stylus tip pretty darn close to the 240mm from the pivot(not easy to measure). Did you find it difficult to set this arm up? Maybe it's a lack of patience but I can't quite get a grasp on the whole "weights on the pin" thing. It seems capable of such minute adjustments but the sheer manualness of the adjusting is like trying to hammer in a finishing nail with a sledgehammer. Take the VTA for instance.

For VTF, I just use a Shure gauge and eschew the hole "weights on the pin" method. I think that is only there for floks who don't didn't have a gauge. Upon checking, the results are the same anyway. In the instructions for the Mayware arm, it gives direction on using the weights and then says "or use a gauge". VTA setting is crude, but I find it no less so than the Rega arms, among others. I have drilled an armboard such that I can fiddle with the spindle-to-pivot distance and will check back or e-mail you with what works best.

On the Sonus Formula IV arm you need to use a high compliance cart. The Shure V15 is a high compliance cart and should be a very good match. If you have your eye on a cart with slightly lower compliance you can use a thicker damping fluid in your arm to compensate. Another poster suggested a DL106, but I believe it compliance is just too low for your arm and not a suitable match.

Do you know if the Grado cartridges are high compliance?