Phono Preamp. With transformer or fully active


What is the difference in sound between a fully active phono stage and one that uses a transformer for part of gain 

I read  discussions in External SUT’s being used and phono stages with built in transformers ?

I noticed that CJ Tea2 has two inputs one is with transformer & one is fully active ?

l also read discussions on fully active 
What is better?   Lol

is the sound softer, more detail , more soundstaging? Quieter?

jeff
frozentundra
lewm

I think you switched things inadvertently, the 30 ohm input is 18.27 xf, I prefer the 10 ohm setting which is 20.68 xf

actual #s from FRT-4 specs:

3 ohm input: xf 35.84; gain 31db, .3mv = 10.8mv, impedance load 37 ohms

10 ohm input: xf 20.68; gain 26db; .3mv = 6.3mv, impedance load 110 ohms

30 ohm input: xf 18.27; gain 25db; .3mv = 5.4mv, impedance load 141 ohms

100 ohm input: xf 10.55; gain 20db; .3mv = 3.3mv, impedance load 423 ohms
I used a Lundahl amorphous core silver transformer and liked it very much. As Mulveling said, they are not as warm as some others - but the clarity! Then I built my own phono/pre, and built a lot of gain into it, so now run my Koetsu platinum direct.

Differences are just an added touch of clarity, added touch of warmth, and added touch of dynamics. So I use the MM input and run the volume at 3 o'clock. Still black silent as a tomb, so there's no down side. But I suspect that if I was using a FET input stage instead of aerospace bipolar (or vintage 6922's), the Lundahl would be notably better.
denon au-320 is very nice, 2 inputs, 3 ohm or 40 ohm gain/loading options, and PASS

https://www.ebay.com/itm/DENON-AU-320-step-up-transformer-mc-moving-coil-cartridges-junk-products-phono/383631324085?hash=item59523573b5:g:f6QAAOSwhtNecvwE

this one, with transformers many people respect, including Bill, has 4 different values set by switch combinations, only 1 input, no PASS for MM (it has only 1 input, so not needed).

https://www.ebay.com/itm/Moving-Coil-Phono-Step-Up-Transformer-Cinemag-3440AH-4-Ratios-1-9-1-36-MC-SUT/124263990235?hash=item1ceeb603db:g:pwAAAOSwdehfBJnw

the EAR MC4, used, 4 variations, via 4 separate sets of inputs, 3/6/12/40 ohms inputs, no PASS, only 1 input, compared to the Fidelity Research it seems poorly thought out, clumsy, were switches thought horrible things?

https://www.willhaben.at/iad/kaufen-und-verkaufen/d/ear-mc4-step-up-transformer-390620595/

a few Fidelity Research FRT-4 are out there

https://www.hifishark.com/search?q=frt-4




I read  discussions in External SUT’s being used and phono stages with built in transformers ?


I thought the OP asked for a phono stage with built-in SUTs.

As for external SUT I found this model very usefull for all cartridges. 
I'm using a jensen SUT with a tavish design Tubed phono stage (mm input). This is paired with the hana el low output mc. The hana is a good match to the jensen, hana calls for greater than 400 ohms, the jensen is at 430 ohms.