SUT vs. Phono preamp

@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.

The Technics SH 305S that Raul mentions is a Amorphous core type . It is a very good sounding SUT as I use one . It comes close to my best LOMC reference a BMC MMC1 current injection phono preamp 

Dear @terry9  : "  But I don't agree about vintage excelling modern.."

well maybe you could be rigth. I don't posted but I listened a system using Lundahl SUT but was a first time I listened to that system and I was in that sessions where the system had mounted a ZYX cartridge that again was the first time I listen that models so I really can't say for sure about that SUT that even I can´t remember its model.

Now: do you already listened to a vintage SUT as the Denon or Technics I mentioned?

Btw, of course that 100khz is a frequency that human beens can't hear directly but I think that " something " is down there with those vintage SUT's for it can goes with that so wide windth FR because if that be easy every one can do it and no today SUT are near of those kind of specs.

Now: "  Even so, my phono-pre is marginally better for dynamics and weight...." I can tell you that between other things the widest flat FR in an active unit is one reason on what you said even that that kind of so wide frequency range is out of our hearing sensitivity.

For many audiophiles SUT's can be addictive. Rigth now I'm listen through my AU-1000 and performs just great and with no noise levels you can detect. Can I ask for more? certainly I can live with for ever but due that my active phonolinepreampis so good in quality and resolution I prefer it  to the SUT but not by a very wide margin.

Music transients is one area where my active unit beats the Denon and from there comes other music main characteristics that SUT can't achieve it however can be near of them.

R.

@rauliruegas @enginedr

I have not listened to any of the SUT’s that you mentioned, but I have listened to some very good vintage SUT’s, both factory assembled and DIY assembled. None was as good as the 1931Ag, and only one was close.

We all three seem to be pretty much agreed, though, that even the best of the SUT’s is not quite a match for the best high gain phono/pre. I suspect that I could not tell the difference between the 1931Ag and a phono/pre using teflon or styrene caps for RIAA - it’s only by using vacuum and air-gap caps exclusively that I can differentiate. I suspect.

@terry9  : I think that for that " differentiate " we need at least two things: room/system high resolution and to know what to look for that could tell me those differences.

Btw, the Technics came from 1981, that are more than 25 years.

R.