Dear @noromance: As you said and confirm the Jelco you own is very good tonearm and IMHO the 997 is no better, maybe different but not better.
What you can do is try your cartridge or cartridges with different headshells: different build material, different overall shape, different weigth, etc. Trying the one that could matchs in better way the cartridge needs and you will know which one because with it the cartridge quality performance been improved.
Other important subject are the headshell wires where you can make an up-grade with better headshell wires and obviously a better tonearm/phono IC cable.
Other subject not less important is that your cartridge/tonearm set up been as accurate as you can. The MINT LP protractor ( inexpensive. ) makes a " difference " for the better if you don't own it. This protractor is made it in specific for the: TT/tonearm/cartridge of each one customer. Unbeatable at any price.
That's what I will do in your place before to think in a tonearm change.
Regards and enjoy the music,
R.
What you can do is try your cartridge or cartridges with different headshells: different build material, different overall shape, different weigth, etc. Trying the one that could matchs in better way the cartridge needs and you will know which one because with it the cartridge quality performance been improved.
Other important subject are the headshell wires where you can make an up-grade with better headshell wires and obviously a better tonearm/phono IC cable.
Other subject not less important is that your cartridge/tonearm set up been as accurate as you can. The MINT LP protractor ( inexpensive. ) makes a " difference " for the better if you don't own it. This protractor is made it in specific for the: TT/tonearm/cartridge of each one customer. Unbeatable at any price.
That's what I will do in your place before to think in a tonearm change.
Regards and enjoy the music,
R.