Upgradability of an MMF-5


I'm aware that there are turntables that are more upgrade-friendly but really want to zero in on this table exclusively for this discussion. What upgrades/tweaks, etc, to this table do you think would make an instantly obvious and moderately to highly gratifying sonic improvement in a system limited to the MMF-5 running thru a 1990s Sony ES series HT receiver running thru JBL L-65 speakers (circa 1977). Any and all types of music in a collection of about 500 LPs but with the lion's share being mainstream Rock (not a lot of Metal), Jazz, and Blues...
lg1
I have a relatively new MMF-5.1 and have not considered upgrading other than a Herbies mat just yet. When I do I will address the isolation with a solid wood base and substitute spikes in place of the rubber feet. Later a cart and possibly look in to fitting one of Projects carbon fiber arms. The cart and phono stage you choose will probably make the biggest difference for you.
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Invest in a new turntable/tonearm.

The MMF-5 is a "buy and listen to without changes" product.

Sell it when you want to upgrade.