''The increased treble'' is well known problem by MC carts. I own
Klyne 7 PX3.5 Phono amp with ''High Frequency Contour'' by
which one can decrease HF by choice. The values between
15 Khz till 40 Khz can be chosen while the needed switches
are marked in the user manual. There is a list with 25 '''well
known carts'' with recommended values. I have no idea if other
phono-pres have similar provision. My other phono-pre; the
Basis Exclusive lacks such provision.