I had a listen to the Utub vid in your O.P. That's almost certainly a synth bass with time & spacial modulation. If it's an actual bass then it's had most of the string & finger noise as well as upper mids removed leaving just enough to give spacial clues for the stereo image.VERY heavily processed.

The older amongst us have ears trained/calibrated by tube/valve amplification via radio/TV as well as LPs all of which have characteristics described by terms like warmth, saturation or fatness.
The reality is that most of that is caused via distortion introduced by the valves/tubes/LP surface and today by deliberately created solid state, tube/valve or digital means.
The dirt added is usually pleasing to our ears as it meets expectations and it involves a lot of harmonics that give a "richer" fatter tone.

An attempt to achieve this on the cheap but seemingly "trad" means is the inclusion of a starved plate tube/valve in a solid state circuit. becasue the tube isn't running warm or hot it won't generate the kind of harmonics or compression that is pleasing but they add some of their native noise to the circuit. In many cases the signal isn't even passed through the valve/tube - just some current to get some noise which is blended in. This rarely works well and simple solid state circuits can do it better - digital processes even more so.
The attached shots of EQ & an amp sim suggest a Marshall amp which is a tube/valve amp which produces plenty of saturation/warmth even when not being pushed. The digital version of that would seek to replicate that.
So I can really get my head around this please let me know what digital model you're using in your amp.
We can assess what that does for your signal and what would, therefore, be unnecessary down stream.


Last edited by rayc; 09/05/23 03:30 PM.
Cheers
rayc
"What's so funny about peace, love & understanding?" - N.Lowe