Diversity of opinion over what

I find it remarkable that what I percieve as cold and analytical others will call warm. Has this ever happened to you?
My particular situation I'm thinking of was that I sold Musical Fidelity A308 integrated amp, some years ago.I thought was just too SS, hard, cold, etc , sounding for my JM Lab speakers.
The guy I sold it to was very happy (I priced it waay low) and said it was very warm as he had expected it to be.
I didn't argue of course, but was really baffled. Even if he used soft toned speakers, by comparison with other amps it really should have been on the cool to neutral side, or am I way off? Beats me!! So I am asking if you have noticed this too? Either way your Warm is another guys cool etc..
I have learned never to argue about this, one guys "ruler flat" is anothers 'really rolled off top end' and dark. I am not equiped like John Atkinson to argue the point empirically.
My assessment of other sonic charateristic has been endorsed by some friends, in particular with tubes which I love experimenting with. I rarely get into a disagreement on tube qualities.
Everyone hears things differently. Different preferences and biases. That is why important to find a reviewer with similar opinions as yours when reading gear reviews in mags.
It's a matter of taste. Benchmark DAC1 in my system sounds very natural and transparent but to many it sounds sterile and analytical. Adding distortion or noise would likely make it sound more vivid same way distorted guitar appears more dynamic then clean sounding guitar. I don't have John Atkinson's experience either but have to admit that Benchmark surprised me with its sound purity making impression of less instruments playing together. Today it sounds absolutely normal to me. As long as we are not talking about bright or unpleasant sound it is better to spend more time getting used to new gear to avoid hasty decisions, especially when it needs long break-in time like my Rowland 102 amp, that sounded best after about 400 hrs.
Years ago, I asked the reviewers from a couple of the mags to publish full audiological reports. I swear a couple of those guys had high frequency loss. I used to have one done every few years. Now I'm old and don't need a test to know I can't hear. That and mi esposa and grown kids tell me so, loudly.
different speaker loads bring out different sound qualities in amplifiers as well

also, tonal balance is a fickle thing and speaker placement and cables etc can change tonal balance in a flash

maybe the persons expectations play into it as well and after time he may change his mind...?
Everyone has different needs and expectations nad likes.
There IS no such thing as reproduced absolute sound.
Naturally some folks will disagree.
I have preferences, so does everyone.
We each find equipment which fufills our needs.
Not someone elses.
It's not just that different folks have different tastes, it's about synergy too. I'm not trying to offend the OP, but I have always found JM Lab speakers to be hard or analytical. I'm sure they would sound their best with some warmer electronics. Speakers that I enjoy, Verity Audio Parsifal Ovations, others have called lifeless or polite. They will be if you put warm electronics in front of them.

It's about balance and synergy. Warm electronics + revealing speakers = good. Revealing electronics + revealing speakers = not so good, and vice versa. Oh yeah, don't forget to through cables into that mix too. I've heard enough different sounding pieces of gear that I think I can take just about any unit and place it with the right accompanying gear, make it sound very good, or make it sound very bad.

Most of us arrive at a similar location via very different paths. Synergy.
Yes, I think that Jmcgrogan2 nailed it. I personally do not use the word synergy (it's a bad word in my vocubulary) but use 'impedance matching' instead but the undelying principal is the same. Electrically the amplifier must be able to drive the speaker it's being connected. And, if the speaker is too capacitative (for example) then the amp must be stable & not break out into oscillations (which is often manifested as harsh/brittle sound), if the speaker is a low impedance load in the bass area then the amp must have sufficient current delivery.
Like Jmcgrogan2 wrote the speaker cables & pre-power cables also make some difference in the sonics.
It's entirely possible that the amp-speaker interface was just fine your case but it could have been the cables or some electronics upstream? Debugging this is a hard & time consuming job but if you do go down the debugging path you end up learning a lot about what makes your rig tick & that is always worth the effort. The easiest thing to do is to dump the amp....
Anyway, the amp-speaker interface has to be considered very seriously esp. for 99% of the speakers in the market that continue to be ill-designed.
I think people have preconceived ideas about products based on other non-truth (other than aural) sensory cues, such as visual, or third party affirmations (reviews). To illustrate my point, these example would possibly spark the ire of those affected by such pre-conceived notions:
1) McIntosh components are cold and analytical sounding.
2) Audio Research components are warm and euphonic.
3) Solid state components are overly warm and tube components are etched and hard to listen to.
Silly? Well, for number three, how many times do reviews of very expensive tube equipment state it has the best traits of solid state amps, and comments on good solid state equipment describe a sound that is not "etched" or in other ways having those negative traits associated with solid state (or, sounds like tubes)?
I think the bottom line is unless you listen to a given piece of equipment with a given loudspeaker, you really don't know how they will react together. All of these biases and preconceived notions really just lend themselves to salesmanship. Sell a product. Hype.
As Bombaywalla says no component is ever heard in isolation; we are always listening to SYSTEMS. I am convinced that there is just about nothing that cannot be made to sound bad by incorrect choices elsewhere in the system. I bought my Apogee Duettas even though they sounded horrible in the store; they are great speakers when set up properly. I agree about the JM Labs; I had a pair of Mini Utopias which could not be faulted for accuracy of sound reproduction but which I was not comfortable with; many others would be. Part of the time I was using my MF NuVista M3 but I had the same impression on other amps as well.
Excellent posts with all of the above comments, and not to forget "speaker-room interactions" too.

Off topic: I noticed it takes a day or longer before a reply is being posted???
I also remember the prior JM labs as being analytical and fairly bright, even for my taste. I think that is possibly the cause of the disparity of opinions in this case. I could not live with those speakers easily without a front end to tame them. The latest series of Focal Utopia speakers are a whole different story. Superb speakers .... amongst the very best of all the ones I have heard in recent years.
How we hear if different for everybody, especially related to culture and language. Many years ago an article appeared in FI magazine that explored how people in the UK and the USA had different 'hearing'. Part of that exploration was aimed at the often used term 'british sound'. Still true, so it is no wonder that we have a diversity of opinion on what speaker sounds 'better'. Recently this difference of hearing is being explored with Asian people.
I suppose I must offer a defense of JMlabs or as we are all seeming to say synergy, taste, preferences, etc. In my constant cycling through gear I ended up with a pair of the original JMlabs Micro-Utopias, more suitable to my new 900sf condo then my previous Alon Lotus's. I ended up through a bit more trial, error, and swapping pairing them with tubed electronics from Deja Vu, a pp EL-34 amp and a preamp. Now if you were to ask my opinion of my speakers I would say they are sweet little speakers that have a nice combination of transparency and warmth. Bright? No way. Is it my room? Electronics? Me? Surely a combination of all of the above, so I guess as they say ymmv. But leave my poor JMlabs alone! Just kidding.
I am not offended at all. I agree that the JM Lab Focals are detailed analytical and have the "Metal Tweeter" syndrome.
I also am deeply aware of the synergystic effects that other elements of the system have on the percieved sound that any one individual component may seem to posess. I found wonderful sound using Tube power amps high caliber copper cables, a tubed pre that uses 6SN7s which I have a fairly large collection of. In all the system sounds still clean and detailed but wonderfully involving and much "warmer". Others may still call the sonic cold steely analytical in the negative sense , but I absolutely do not hear it that way any longer.
One salient fact though is that there was some agreement on the characteristic sound of the speakers! So you see there is some agreement in certain situations.
Thanks Steve
But Steve, you did say the sound with the MF A308 was "hard, cold" which I take for detailed and analytical, when paired with your JM Labs speakers. I'm sure that tubes can tame the JM Labs speakers, but that doesn't mean the MF A308 is any guiltier of being hard and cold than you JM Labs. Mate the MF A308 with some warm, musical speakers and the sound would probably be fine.
analytical speaker + analytical electrics = Bad.
wam speaker + warm electronics = Bad
warm electronics + analytical speakers = Good
analytical electronics + warm speakers = Good.

Are you starting to see where I'm headed with this? Yes, the room and cables come into play too. A live room probably needs warmer gear while a dead room would prefer more analytical gear. It's all about system matching.

I mean I know what your talking about. I had a Mark Levinson No. 38S preamp in my system once and it sounded terrible. My wife even noted that "her car radio sounds better than that". I sold it to a guy who loved it. I don't think that ML is bad, it just did not work at all in the system that I owned at that time.