Should the best systems sound almost identical?

Mceljo,
"Personal preference" is determined by one`s hearing and processing(ear-brain). Ears are always in the equation.

Without ears there`s no perception.
Best Regards,

planar speakers do not sound like cone-based speakers.the dispersion of sound differs between driver types.

also it is possible that tube and solid state based systems will sound different.

Charles1dad - Ears are always in the equation, but is a constant unless you somehow manage to changes ears. Personal preference matters in the real world because we can't match the original sound exactly.

An idealistic listening test for a speaker/system would be to have a singer in a room that is also being recorded. The recorded sound would be played back through the system on deley providing the A to B comparison. The best system would be the one that most closely matched the original sound at the listening sweet spot, but that doesn't mean that it would be the preferred sound in any other setting.

If I was Bill Gates I'd waste my money setting up some listening events along these lines just to see what happened. If money were no object it could be fun. It might even be possible for vendors to come setup in identical rooms so you could see which system most closely approximated the original sound.

Let's, for the sake of argument, take an extreme position:

Look at it this way: would you expect that one $2+ million Stradivarius violin will sound the same as another? Or as a $1,000 violin? No, I would argue, of course not. Yet, they are all made, to the greatest extent possible, to be physically identical; the goal is to make violins that are physically and acoustically the same. Try as we might, can’t be done.

So, why should we expect any two speakers – let alone any two speakers that are physically, electronically, and acoustically radically different – to sound the same reproducing the different sounds produced by intentionally identical instruments? It is, I would again argue, entirely (physically, in accordance with the laws of physics, etc) impossible. Full stop.

Try an extreme: if “neutral” “transparent” “100% invisible” “disappearing” or any other manner of verbiage amounting to the claim that this X, Y, Z is so unspeakably wonderful that it simply vanishes to present one with an uncolored magical connection with the true essence of whatever is recorded on any given random piece of software turning in circles someplace in the chain were anything other than meaningless marketing pabulum, then why not take one of your Focals, mate it with one of your MBLs, and call them the perfect stereo pair. Hey, if they are each the perfect realization of some platonic ideal of sound reproduction, mix and match: no worries. Unthinkable?

Or another take: a tweeter blows on one of your speakers. Do you replace it with a Rat-Shack, off the shelf tweeter of the same size and specs, or do you get as close to a matched replacement from the manufacturer or, barring that, scrap the working one and reinstall a matched pair? (Verity, e.g., keeps records on the specs of each an every driver they ship in order to be able to supply a matched mate for just this occasion). So, identical enclosures, identical electronics, slight variation in a single driver = completely unacceptable – yet we’re discussing whether two things that are 100% different in every way could sound so close to identical as to be interchangeable?

Clearly, I have an opinion on this one. Put me firmly in the camp believing that uncolored, “objectively true,” musical reproduction is a myth. Marketing nonsense. Yes, it is the goal. Yes, we all chase it. Yes, one might inch ever “closer.” Yes, one may honestly believe that A is objectively “more invisible” than B (while their neighbor believes the opposite…). But it’s a lie. Everything adds color. Every design is a product of choices, and each choice has an impact. Enjoy – revel in – the boundless pleasure that music brings to life; the infinite variation of each voice, instrument, the equipment used to record, the choices made in the mix, and gear used to reproduce them all. But, really, let’s not kid ourselves.

Anyway, that’s my story, and I’m sticking to it. (And yes, all that said, I certainly believe that my present setup is more “real” than any other I've had before, and various manner of possible alternatives. Inconsistent? Hypocritical? Meh....I’ve been called worse.)

If the goal of the system is to reproduce the input signal with minimal coloration, then the answer is systems should trend toward sounding alike. To make the issue clearer I would reduce it to "should power amplifiers sound alike?" Power amplifiers are not cars, wines or women -- they are audio amplifiers supposedly designed to reproduce the signal feed them at an amplified level. In the real world even amplifiers do not sound the same. I could argue that the differences between competent, high quality amplifiers is quite small, but I think a better explanation is that many audiophile amplifier manufacturers don't want their amps to sound like other amplifiers. Their amps are not intended to be neutral sounding products. At the system level I suspect audiophile are also not trying to put together neutral sounding systems, hence there is little convergence in sound quality even as prices climb. As a group, audiophiles use their systems as a form of personal expression. It's something that reflects the audiophile's tastes, sophistication and preferences.