High end stereo preamps? Worth it?

Surely its not just more components adding more ’noise’ - its a question of WHICH sort of components and WHICH sort of circuit implementation, no?
Maybe a drastic example of my own, a run of the mill mid/low-fi Rotel preamp I’d replaced by a Levison no. 326S preamp.
The difference like day and night. Maybe hard to believe - but that’s what can happen, and I’m pretty sure will happen - so long you own speakers, amp etc. that will match the ’new’ setup.
Cheap shoebox speakers and or low-fi amp will possibly just paste over the difference.
So as always it’s ’horses for courses’.
And the best expensive cable will NOT make any difference with a low/mid-fi preamp. Tried that of course too. Nada.
M. 🇿🇦

clearthinker129 posts

Many posts saying hi-end preaamps improve sound.
One post saying 'why', surely the additional circuitry cannot improve the signal it is fed with. Doesn't it just add noise?
Or does it add some aspect to the sound that these posters find pleasing?
Can somebody who understands the tech please tell me.

Many have posted how a quality preamp improved their systems.  None will be able to tell you the science.  To many of us, It just sounds better..  Bascom King, in his interview on inserting a preamp, states "the music is more compelling and real"  Compelling and Real.  I don't think we will ever measure these qualities, but I know I can hear it, or at least I am convinced I am, and convinced enough to own a nice pre amp. 

First- one premise made by the OP is incorrect- phono stages are not noise free. Some are very quiet but none are dead silent. 
Next, I’ve been messing around in this audio world since the 1970’s. Everything makes a difference and a great preamp can make a system and a dud of a preamp can break a system. More so, I believe, than can different amps. 

IMHO.... It has probably made the most significant change in systems I have owned in the past 35 years.
1980 Something... DQ-20 speakers, Adcom GFA 555, Amp GFA 565 preamp SOTA sapphire TT  ..
I went from the Adcom GFA 565 to a CJ Premiere 2.
I was completely blown away didn’t need to do an A.B. test...That was the catalyst that put me on the quest for Audio Nirvana.
YES !!!!! 

I think you need a decent preamp in any system.  I used to have an Audio Research Hybrid Preamp in the early nineties and for my DAC I have the Wadia Digital.  I loved my Audio Research until it broke after three years of use.  While looking for a replacement or trying to have my preamp repaired locally, I used my Wadia Digital which has a volume controller  temporarily thru my Krell  amp.  The sound was not as warm  with the DAC preamp as my Hybrid Audio Research  so I ended up going for the newer products. Now  my Preamp is solid state now which is a NuForce and I also switched my DAC to the Benchmark unit .  My Wadia is still in use in my bedroom system .  So the answer is a good preamp is vital to a good system and better as a stand alone than a preamp with DAC.

imThorek