A warm DAC?

If you can get your hands on an Akiko Audio Squeeze Box, that’s supposed to make any solid state component sound tube like.

larseand OP
Prima Luna integrated

This "could" be your problem, HF transformer oscillation that rings like a bell. Starts at 10khz and shows in the square wave also. Especially with the Focals metal tweeters, it may excite them with hf sibilance etc..
https://www.stereophile.com/images/1214PLDPIfig01.jpg

See how the Focals are very high some 18ohms in impedance in the highs, this is where the Prima Luna also rings it ’s worse with high impedance.
You could "try" not too loud to load down the output of the Prima Luna just to see, with a 2ohm 10watt resistor this will then mimic the green trace which is flat.
https://www.stereophile.com/images/archivesart/707FOCFIG1.jpg

Cheers George

AMR DP-777. Amazing analog sounding DAC with tube input (on SPDIF), R-2R (on redbook and 96 kHz), AND delta-sigma (on hi-res).

Burl B2 Bomber. Musical and involving with Oppo transport. Right at yr 2.5K price point. Audiophiles should check out pro gear. Better sound at lower prices.