step up transformer for make up gain?

[extraware]

I am using 4:1 [10k:600] Jensen input transformers in my 'EAResque' eq to drop the levels, thus avoid/lessen LF inductor saturation.
My first post on this project, which has a link to the forssell schemo and pics of the filter boardsHERE

The filters will use a single opamp gain stage a la the forsell scheme. I need to figure out where the best place is to make up the initial step-down...I just barely know what I am doing here, so forgive me if it is obvious :? , but I see that it is/may be possible to:
(1) use the filter opamp for makeup too? or
(2) have an active output stage with make-up gain. or
(3) use a step-up output transformer to match the step-down input?

Any comments on the trade-offs? It seems to me that a step-up output transformer may be an elegant [read simple] solution, but it does not seem to be a common one-perhaps for good reasons?

 

[Svart]

a step up is fine but you have to look deeper into how you are going to drive that trafo. stepping up voltage means you need more current drive..

 

[extraware]

Cool. Can you point me to some reading on this issue? So far, I am looking over the Jensen 'typical application' schematics for their step-up output transformers....and trying to catch a clue :wink:

[for inputs I am using 2xJensen jt-6110-b]

As an elementary aside, what are the fundamental design differences between an input and an output trafo?

 

[gyraf]

As an elementary aside, what are the fundamental design differences between an input and an output trafo?

Output transformers can be driven from a known (and often very low) source impedance. This often makes it cheap, simple, and wide-band.

Input transformers has to be designed to accept a variety of (often med-to-hi Z) source impedances, and thus becomes expensive, complicated, and bandwidth-restricted.

(this is a very simplified version)

Jakob E.