SUT experience

There is no real sound benefit from a SUT, a Phonostage is very very capable of presenting a recording in a away that is satisfying for numerous listeners.

A SUT 'will' add a Richness in Tone to a replay when used as a comparison to a typical MC Stage.

SUT's are generic in their voicing, the Rich Tone being perceived can be scaled from a Hint of Richness ( a tight fast decaying Bass Note is maintained, maybe a little underpinned with weight) through to a Very Noticeable ( very loose Bass Notes with a extended presence, possibly, depending on the individual listener, this Bass Type treks toward the point of being overbearing).

A Head Amp of the designs I have heard in comparison to a SUT, can be described as being leaner in the voicing than the leanest SUT types. A Head Amp can be more in liking to a MC Stage.

To date, as a personal experience, I have not discovered a Phonostage that has been encouraging enough, to not use the options for voicing a Cart's produced sound via a SUT or Head Amp.      

A “head amp” or “pre-preamp” is simply a linear active gain stage to boost the cartridge output so the ensemble can then drive an MM stage. If you start with a high gain MC phono stage, there’s no role for a head amp. And a head amp, like a SUT, requires the insertion of additional connectors and cables in the signal path.

Correction Required

My statement should have been,  " SUT's are not generic in their voicing, "

Welcome to the SUT experience! IMO a good SUT sounds like "music" and further differentiates vinyl’s sound away from digital.

There are many different SUTs, each with their own distinct sonic character. Choosing the right ratio for a given cartridge is extremely important - much more than loading considerations. SUTs with 2 or more taps are very handy. My general-purpose favorite SUT is the EAR (MC-3 and MC-4; 3 and 4 taps respectively).

There is perhaps even more variance in the sound of various MC pre-preamp stages/SUTs that there is with RIAA MM stage - though the latter is crucially important as well.

JFET (voltage) pre-preamps can also be excellent in the right setup. But most of them tend to sound more "sterile" than SUTs. I like Jim Hagerman’s various Piccolos because they sound good and are cheap, at the expense of a bit higher noise floor (not problematic IMO). Most are JFET (voltage) based but he just added a Piccolo Zero model that is trans-impedance (current) based. I have one on order to try :)

Dear @lewm  : It's obvious that you never read the Stellar review I linked where the reviewer compared it to a 30K+ phono stages.

The " raining " in the @adrianleewelch  parade is because the PS Adio is better than the Project too and way better that any SUT.

Btw, @mulveling   " SUT sounds like "music" and further differentiates vinyl’s sound away from digital. ":

I'm not against you but your statement is only what you like and not what is rigth. You like SUT's thanks to its higher developed distortions and it's not your fault. Issue is that our ears perception are way tolerant in different kind of distortions, the VIV tonearm is an example how tolerant ( it can't discriminates ) to higher distortions are the owners ears and again no fault in those owners: that's what that's, ears limitations.

R.