Well I have already received by mail the necessary to put the negative connector that enters the switch with ground.
To test it, I removed the Entreq cable with RJ45 connector from the switch, so that the swtich remained without any type of ground connection.
I heard in these conditions the first movement of the quartet of string MWV R18 of Mendelssohn in the performance of Melos Quartett and recorded by DG. It is a recording with a brilliant sound, which can become annoying.
When I connected the ground wire to the negative pole of the connector, I noticed a larger body in the music and decreased brightness.
I withdrew this connection and went back to listening without connection to ground.
After a while I connected the Entreq cable with RJ45 connector to the Switch and its Entreq Silver Minimus box (in a few days the connection will be to a Poseidon) and it happened again the same as when I connected the first cable described above. This means that the Entreq box was already doing a good job.
Then I also connected the wire that gives ground to the negative connector that is introduced in the switch and then there was an additional improvement in musicality and reduction of the digital stress.
This is how I like my system and how it has finally been.
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