Cartridge upgrade, something warmer


I love my Dynavector 20XL on a Rega P5 but its a little thin at times. Lots detail and depth but cool. This is matched with a Dynavector P75 all Arcam FJM electronics. Benz Glider, Ortofon Bronze or ????
Maybe I should try a phono preamp first. All suggestions welcome
fourgirls
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As Elizabeth suggested, try a different loading. It is free and can make a dramatic difference. The other thing to try is to change the vertical tracking angle (VTA) of the cartridge (if your arm allows for this). Thin sound is associated with too high an angle (the arm is tilted downward from the pivot).

When dialing in a cartridge, I adjust both VTA and loading. They are sort of interactive in that they roughly do the same sort of thing, in terms of tonal balance, but not quite. That means adjusting one may change what is the optimal setting of the other. By increasing the loading (LOWER value resistor, such as 100 ohms vs. 47,000 ohms), you will tend to reduce sibilance, tip the tonal balance toward the bass (less cool sounding), but going too far makes the music sound slow and muddled and lacking in top end "air" and extension. The same would be true with lowering the VTA, but with less impact on the bass response. Some mix of VTA and loading adjustment will be the best compromise.
It's not the cartridge.

Elizabeth's guidance is definitely the first thing to try. Then adjustments to your arm/cart setup. Then cheaper tweaks like TT mats (felt is horrible, though slippage wouln't usually result in thinness), clamps, etc. All as advised above.

That said, some Arcam gear can be thin sounding (owned their top CDP, sold it) and all SS gear can except at very high levels. Even there it is when compared to comparably priced tube gear. That's a path worth exploring but I'd do the cheaper stuff first. Everthing you learn will train your ears and inform your decision-making ability when it comes to costlier upgrades. You'll make fewer mis-steps.

Again, it's not the cartridge. A Grado would provide lots of artificial warmth, but Grados on Rega rigs have a long history of annoying their owners. If you must experiment with warm sounding carts I'd try some MM's. Not much money and Raul and the MM crowd could advise on suitable choices.
Some good advice posted on here.
To which can I add; try to find an original ARC Ref phono for its warm, tubey sounds and cartridge wise add a Koetsu Rosewood to your collection.
Are you using the PE mode on the P75? I had that combo for a couple of years and it never sounded thin to me. I found the P75 to be lacking something with other carts, but in PE mode with the 20XL it was wonderful.

Now, if you are in PE mode I would suggest what Elizabeth recommended and try to go lower on you settings on the P75.