I assume you have heard CDs or Streaming thru the other changes.
You never know what that new cartridge would have sounded like on the Rega, or thru the prior equipment.
Where’s the old cartridge? I’d get a spare headshell and listen to it on the Technics. That will teach you something about the phono stage change. I always say, when it comes to Phono, it is ’Preferred’ not ’Better’, and try to have return privileges.
I arranged a re-tip of a friend’s Benz Micro Ruby Wood LOMC, and played it here enough hours to ’break it in’ before comparing to other cartridges. Thru my SUT and MM Phono that I have heard all cartridges, mine and friend’s, thru for years. i.e. no other changes, just the cartridge.
I have 3 arms and can play all of them simultaneously (staggered positions to play the same content just heard), so I can compare within seconds.
It sounded ’thin’ here.
This past week, I went to his home, installed and played it thru his system, it sounded very good there, played thru speakers I used to own and am very familiar with, having heard them in his system before. I think the difference was his SS Phono Stage, mine is via a Vintage McIntosh MM Tube Phono input.
I was very happy for him, and it taught me something by ear rather than words.
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Interesting to read that you are aware of the Rega VTA/Shims, and decided not to bother, and it sounded quite good to you.
My personality, I would have to get the shims, and it took me a lot of persistence, but I now know the overhang and two null point measurements for the Rega RB880 arm (and others)

