Ohhh, gotcha's now Ed, thanks
Even clay'ed, the JVC needs to have that awful ringing platter damped down, too. The rubber mat really doesn't do it....I have spray coated the inner platter with a light layer of plast-i-clay as well, and have an AQ sorbothane mat
under the Herbie's on mine. Along with the clay inside.....the whole she-bang is also carefully set up on a 4" maple block.
Unless BB changed it out, he's got the
Grado Gold....with incredibly chintzy
bonded (not nude) elliptical tip....the type AT sells in their $29.00 cartridges
To shine, they need to be damped with 1000cst silicone on the coils, given a van Alstine Longhorn and they need a shibata/line stylus. As with London cartridges and as TheCartridgeMan has found on his gussied up $1200.00 Grado Gold - these moving irons lack adequate tracking unless they have a shibata/line or other
over-extended hyperelliptical stylus.
It's a lot of work to get a Grado to sound perfect.....more than any sane person should bear. Me, I'm certifiable

Your
AT150MLX might be the pinnacle of high-output moving magnet designs ever made...no wonder
your 1200 trounced the JVC.
Hope to meet ya' (and you all) at a near future event. I'm moving from here by April 1 so onward to find a new listening spot and abode for me.
Thx, John