SUT vs. Phono preamp


On what basis is  the decision to chose  a SUT vs. a phonostage made?
boofer
I have auditioned a home-made (not by me) Sowter SUT which sounded very dynamic but could not achieve the correct tonal balance.  It couldn't have been an impedance mismatch as it was rated at 220 ohms the same as my current Audio Interface.  Something else apparently.
@andirocks , IMO materials are far more important than brand; further, I trust the Lundahl brand far more than Cardas.

In any case, my experience is with the state-of-the-art Lundahl 1931Ag.
Dear @terry9 : materials is always important but I think that the more critical and important characteristics belongs to the rigth build transformer design and the quality level for the excecution of that design.

Audio Note uses pure silver inits SUT’s and are not so good in quality level performance even its FR goes only at 50khz.

Design/manufacture SUT’s is no rocket science but more knowledge level and skills to do it.
Vintage SUT’s excells in those both characteristics and you have many examples:

Denon AU-1000 is only one of them and uses no silver, Audio Technica AT100T is other excellent unit ( I owned when I owned the AT1000MC where that SUT was dedicated for. ) with wide FR, Ortofon T-2000 silver wire and 4hz to 150khz, Technics top SUT is the champ on FR windth: 3hz to 300khz.. In this regards Lundahl is only average even the Ag version. Of the examples I mentioned only the Ortofon use silver wire.
I owned/own all those SUT’s but the Technics and I forgot and still own Entré that’s really good vinatge SUT.

In those old time existed a very hard SUT competition between manufacturers and this kind of contest made it that each brand tryed to be the top one.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

Btw, some one mentioned Luxman, well I owned the Luxman C5000A Phonolinepreamp that came with the 8020/30 silvber wire SUT's and were and are really mediocre and nothing to look for. Of course in those old times for me the C5000A was a premium unit but for other reasons not in specific for the SUT.
@rauliruegas ,

materials is always important but I think that the more critical and important characteristics belongs to the rigth build transformer design and the quality level for the excecution of that design.

I agree. I tried to say that in the sentence about trusting the Lundahl brand more than the Cardas. You said it better.

But I don't agree about vintage excelling modern. As I understand it, amorphous core (Metglas) has only been understood and available for the last 25 years or so. Also, modern machines allow for more precise tensioning and placement than previously, hence, at the very least, more consistency in manufacture.

As for FR, 1931Ag's are 10-100,000 Hz =/- 1dB, which is more than adequate for a puppy's hearing, let alone mine; and I trust Lundahl's current testing and reporting more than vintage.

Finally, my testing shows the 1931Ag to be pretty close to pure gain. Not a whole lot of room for improvement there.