@tobes P77 is great with its original stylus, i never tried JICO on Garrott, but i’ve been using SAS on my Technics cartridges.
My old Garrott P77 with original stylus was stunning on Reed 3p "12 tonearm (18g mass), i couldn’t get the same quality on some other tonearms though.
You could try the latest Garrott stylus for your old P77.
Regarging Garrott cartridges i asked Philippe Luder (Managing Director in Australia):
"The principal difference between the two Cartridges is the Stylus Assembly. The Ps-77i is fitted with a Micro Scanner MKII diamond and tuned accordingly. The Ps-77 uses a Micro Tracer Diamond.
The sound of the MSMKII is more extended at both ends of the Audio spectrum therefore sweeter treble and deeper bass with overall flatter Frequency response."
My old Garrott P77 with original stylus was stunning on Reed 3p "12 tonearm (18g mass), i couldn’t get the same quality on some other tonearms though.
You could try the latest Garrott stylus for your old P77.
Regarging Garrott cartridges i asked Philippe Luder (Managing Director in Australia):
"The principal difference between the two Cartridges is the Stylus Assembly. The Ps-77i is fitted with a Micro Scanner MKII diamond and tuned accordingly. The Ps-77 uses a Micro Tracer Diamond.
The sound of the MSMKII is more extended at both ends of the Audio spectrum therefore sweeter treble and deeper bass with overall flatter Frequency response."