Recommandation for 1:6 1:8 SUT under $5K?

I forgot I made this 'SUT INFO' on this site

https://www.audiogon.com/systems/11318

I just used the term X Factor I found on this chart

then I made my own chart

@elliottbnewcombjr 

it took me quite a while until I found the actual specifics of gain that occurred at those designated positions for my FRT-4 SUT.

Turns ratio and gain (X??) are not the same thing and the two only match when the load impedance is infinite and the source impedance 0.  The chart you present seems to use gain, X and turns ratio as the same number which can lead to confusion.   The turns ratio is used for impedance calculations and the gain is the result of applying the related impedances to the turns ratio.

Consider the Altec Peerless 4722.  This transformer has 1:18 and 1:36 turns ratios.  If you feed it with a Denon 103 (40Ω) into a typical 47kΩ,  both turns ratios will give about the same gain (X) of around 23-24dB and not the expected 25dB (1:18) and 31dB (1:36).

The above case is extreme and using the X factor for calculating impedances will not assure accurate results.  Of further interest, in the case of the 103-4722 combo, many (including Mitch Cotter) find the 1:36 position to be better sounding than the 1:18 even though the 103 is being loaded at a value below its internal impedance.  

dave

Given the specs, how/who came up with 3/10/30/100 for the designations?

I'm sure they moved over to Sony's camera division, and continued their mission 

intactaudio

Tomato, Tomato, I hope you can hear the difference.

call me stubborn, persistent, but only because otherwise it makes no sense to me.

The OBJECTIVE is to increase the signal strength.

The RESULT of the OBJECTIVE, is a change to impedance (unless separate controls are provided)

you said "The turns ratio is used for impedance calculations and the gain is the result of applying the related impedances to the turns ratio."

I'm saying, in SUTs like mine (impedance is not a separate control), the impedance is the result, I call it 'resultant impedance'.

In my world, GAIN (shown as a ratio), i.e. 1:20.68 is a shorthand way of saying x-factor of 20.68. You refer to 1:20.68 as 'turns ratio', I, and the chart refer to it as X-Factor

In my world, they are the same, and the only way you can know the 'resultant impedance' is to start with the x-factor and then do some calculations.

@elliottbnewcombjr 

I'm saying, in SUTs like mine (impedance is not a separate control), the impedance is the result, I call it 'resultant impedance'.

In my world, GAIN (shown as a ratio), i.e. 1:20.68 is a shorthand way of saying x-factor of 20.68. You refer to 1:20.68 as 'turns ratio', I, and the chart refer to it as X-Factor

Impedance is a defined term with simple known calculations.  You cannot take the gain in circuit and use it to accurately calculate impedance.  Gain and turns ratio both terms that have different definitions and conflating them into a single term "X-factor" only leads to confusion.  

Take the case I outlined above for the peerless 4722 in combination with a Denon 103R and a 47kΩ MM phono stage.   The impedance numbers printed on the can are 38/150:50,000.  Below I have shown the basics of the two connections and I ask you what the X factor is in both of these situations?

38:50000

Turns ratio 1:36

Gain  24.1dB

150:50000

Turns ratio 1:18

Gain 22.8 dB

dave