What is meant exactly by the description 'more musical'?

that statement seems to me as if you are the only audiophile that do that.

I dont doubt that most audiophiles plays with room acoustic in a way or in another ... I am not alone ...

But there is difference of level and control between putting panels on a wall and designing and distributing resonators in a room and all other mechanical possibilities without forgetting the electronical one as EQ and DSP as tools ......

And reading threads i know for sure that many audiophile confuse acoustics with room acoustic , and not only that but reduce room acoustic to a few panels installation ...

One thing is sure : "musicality" is determined by the relation between the system/ room way more than by a gear upgrade in most case save if a piece of gear is way worst than the other pieces ...

Musicality which you claimed is only a subjective arbitrary taste is precisely determined by the control of all acoustic factors ...Not only by the amplifier design etc ...

I deduce from my experiments and reading threads that more than half of audiophiles at least ignore the huge impact of acoustics conditions and controls over their gear fetichism ... And they call their gear fetichism their taste and they claim that it is the main source of musicality , their gear choice branded name favorite win as being the most important factor of S.Q. not acoustics ...

musicality is not only a subjective perception it is an objective set of correlated conditions and controls parameters in the system/room ...

As for acoustics basics , electrical noise floor control and mechanical vibrations controlos together are on par in importance with gear choice at any price ...I spoke about perceptual impact ...

The reason for that is simple : most people dont have the dedicated room to play and learn with and the gear user manual is simplest to peak into and understand that the very complex concepts of acoustics ... 😊

Musicality is characterized as a mere subjective taste only in this case of acoustics ignorance ...

Musicality levels are acoustical states of a system/room under controls at any price....These controls depend on parameters not on taste only and essentially ...

It takes an acoustician to observe the level of acoustic information degradation caused by crosstalk between all stereo speakers nevermind their price , gear designers when they observed it, proposed only very partial solutions ... Dr. Choueiri solved it ...

This has noting to do with taste and is at the core experience of what musicality is about : timbre experience, immersiveness and spatial dimensions of acoustic information ...Nothing here is about taste ...

Acoustics as medecine is grounded in  science but own  a heart : an artform and practice ...

When I think of that term I think of bouncy and strong mid bass with easy highs. 
 

A person that listens to classical or vocal music probably has a very different meaning of musical to mine. 
 

Kind of an overused term that doesn’t mean much IMO. 

A part of acoustics is about what are the factors of "musicality", then not as a mere taste without content or meaning, but as a  precise set of  controlled  factors contributing  to subjective perception experiments ... Musicality is objectively desc- ribed by acoustics and psycho-acoustics ...

Read about it ...

Kind of an overused term that doesn’t mean much IMO.

Alrighty 

Once we agree speakers and components can interact with varying results then I can say something is more musical 'in my system' without hurting anybody's feelings. 

When I bought the Hegel H360 I had a pair of Revel salon 1 speakers and of everything I could fford the hegel was the most musical 1, Allowed the speakers to play dynamically without adding emphasis to any fq or dulling others. Some competition made the salon sound chesty, some made the top end sizzle another didn't allow the bass to fill the room, so with those speakers in that budget the h360 was the most musical. When I upgraded to the Salon 2 I lost that musicality to a clinical, anemic, bass light sound that, while doing some things well didn't create a believable sound. 

Musicality is about room, speaker and component matching. Some experts say dsp can compensate, but I've never found a dsp able to change a speakers fundamental sound enough to fix the room and component misalignment instead you get a flat measured response lac king in dynamics. I'll qualify this with. Component matching for great results can bankrupt the average Joe.and with that consideration developing a relationship with a dealer can save money in the long haul.