New Cartridge Time

There are much better cartridges than Grado available for your tonearm.

But using low compliance DL-103 on Rega is just a demonstration that you don't understand tonearm/cartridge matching theory, read here.  And your dealer too. 

You tonearm effective moving mass is .... ? 

Thanks, I don’t understand. Give me some suggestions for the Rega RB 330 tone arm that would match well in the $750.00 range.

Ok, SONY XL-50 with Boron Pipe cantilever and Hyper-Elliptical stylus tip.
Excellent MM cartridge if you can find NOS sample with genuine stylus.
It was one of a few top MM from SONY in the 80’s.

You can also look for new mid compliance Garrott P77i (price in AUD), this is stunning latest version of the legendary P77 from Garrott Brothers.