Audio quality with sub-master

Hello everybody.
Has anyone of you ever noticed that with the use of sub-masters, the audio quality loses definition?
I state that I have been using cubase for a very long time and I am fine (I started with atari … then cubase 5 vst, cubase 5 etc … and now I use cubase 11).
I skipped cubase 6 to 9, so I have no info on those.
I started to notice on cubase 10 (but it is also valid for 10.5, 11 and 12 that I am trying in these days in trial mode), that if you pass the audio from the sub-masters, the quality degrades.
If, on the other hand, you use VCAs, and you send everything to the out directly, the quality remains the same.
In particular, with sub-master, the sound “closes” also as spatiality and as dynamics.

I work with PC (Intel I7 7820x), 64 Gb ram, NVME HDD, Focusrite 18i20 3th gen sound card, 64 bit 96 KHz audio.
I found it both on recorded audio and on VST instruments.

I noticed it using live speakers: the front is made of 2 HARP BMB 4015 and 2 QSC PLX 3402 power amps.

with normal speakers, you don’t notice it much, even if the most attentive can also notice it with headphones.

Has anyone ever noticed?
Are there any remedies?

Thank you and good job to everybody.

Have you done a null test?

No offense, but you’re probably wrong, and it’s probably easily provable that you’re wrong.

Like mlindeb implied you should do a null test if you haven’t already. My hunch is that you’ll either get a complete null or one that goes so far down as to only show quantization noise far below the noise floor of any realistic listening environment.

What are sub-masters?

Group channels?

Maybe… maybe not… sub-masters (as used in broadcast consoles) are different, normally.

I call them sub-masters (typo from live mixer) but they are the channel croups (the blue ones) from cubase.

About the test: it was not a test.
it is a condition that I have encountered.
I state that I am not saying that cubase is not good: I love it.
I say that I noticed that if channel groups are not used, the output sound is “more airy”, more dynamic, less closed (audibly).
when I noticed it, I tried on several tracks (about ten).
And if you listen to the song prepared with the channel groups compared to the one prepared with the VCA (without channel goup), they sound different, and the second (VCA) is much more “beautiful” as a listening quality.
since then, I do everything with VCAs, and only when new releases come out, do I “try” the channel groups, but for now it is always better to use only VCAs.

What we were trying to say is, that the groups (subgroups in live sound) should not change the sound.
OTOH it is a summing bus before the final summing.