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
A lot of SUT's offer several settings, the Denon AU-320 has two, 3 ohm and 40 ohm. The Fidelity Research FRT-4 that Elliott just purchased has 4 settings so it covers a large range of carts.
A lot of hum and noise can be traced to poor planning, placing it next to an amp or other high power device along with running the cables close to power cables.Both Elliott and I were careful of our installation and are happy to report totally silent operation. A SUT that is set up carefully can be much quieter than an active phono stage. The quietest active MC phono stages usually cost big bucks as well.
BillWojo
Do you have a MM phono input now or phono preamp now, MM and/or MC? Options?

I recently asked for help here, 3 separate threads, and got good advice as usual

I started by looking for a separate Phono Preamp for my office, 2 TT, wanted two inputs, for 2 MM cartridges.

https://forum.audiogon.com/discussions/phono-eq-small-inexpensive-two-phono-inputs

I bought the Cambridge Audio Alva Duo, nice features

https://www.amazon.com/gp/product/B07932QK4N/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Then I bought this inexpensive Pyle, MM only

https://www.ebay.com/itm/PYLE-PRO-PP999-Phono-Turntable-Pre-Amplifier/362969672529?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Pyle’s MM sound was the same as the Cambridge, my plans changed to only 1 TT in office, kept the Pyle, returned the Cambridge. If I needed 2 TT, the Cambridge has nice features for not too much money.

...........................................

Then Bill tempted me into the MC world.

I checked cartridge specs: new; vintage; damaged to be fixed by Steve at VAS, and chose a new Audio Technica for my first MC cartridge, AT33PTG-II, I absolutely love it.

https://www.amazon.com/gp/product/B00475S0BU/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

........................................

My McIntosh Tube Tuner/Preamp mx110z from the 60’s has two MM Inputs, and it sounds great, so why skip it with a new external phono stage if a SUT would boost signal enough for my existing MM inputs?

sooo, Which SUT (I started knowing zero, ended very well informed). In that thread, I posted links to various SUTS with various features, as well as the others members suggested.

https://forum.audiogon.com/discussions/which-sut-for-3mv-10-ohms-mc-cartridge-into-3mv-mm-input-sensiti

I like options for the future, and have two tonearms, so 1 MM arm, 1 MC Arm. PASS lets you use the SUT as a switch for MM, so 2 cartridges into 1 phono input.

After learning, and finding this Fidelity Research’s options and features, and preferring Vintage, I took a chance on it, glad I did.

https://www.ebay.com/itm/Fidelity-research-FR-FRT-4-Toroidal-Transformer-In-Excellent-Condition/333648114135?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

3 separately selectable inputs, 4 selectable gain options, and PASS.

I plunked it down, zero noise. compared my new MC to my existing MM via PASS.

Yesterday I moved it to 3 other locations to find noise, could not do it.

10 ohm 21x, and 30 ohm 18x gain choices are very good for this cartridge. Bill, Arne and I all preferred the 10 ohm/21x factor setting for my .3mv/10 ohm cartridge, which gives 6.3mv sig (before losses), 110 ohm load to 47k phono input. (all gibberish to me before learning from members here). That leaves me a very high gain 36x and a low gain 11x option for the future.

....................................

Answer: if you don’t have a phono stage, a flexible one, MM PASS, MC with optional gain (front or internal switches, not resistors) would be nice.

btw: I borrowed my friends highly regarded Rowland Preamp, it was huge, a separate power supply, and sadly damaged, sounded awful.

btw: Prior to this McIntosh mx110z tube tuner preamp, I had a highly regarded McIntosh SS C28 preamp, had it and my Mcintosh SS amp factory overhauled. I actually preferred the AT120 TT’s little dinky built-in phono preamp’s sound to the C38’s phono stage.

So, what sounds best? It takes trial, make sure you can return what you try.

best of luck choosing,

Elliott





Elliot, Not that it matters one iota to the performance of your system, but I get a reflected input impedance of 145 ohms (not 110 ohms), for your 1:18 step-up ratio into a fixed 47K ohm load resistance on your Mc phono stage.  And a step-up voltage of 5.4mV, not 6.3mV.  This is assuming that when you write "10 ohm/18X", you mean to say that you are using a 1:18 step up ratio.  Like I said, the numbers are so close that the differences don't matter, but I wonder how you made the calculations. 
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.