output trannies

[flodge]

Hi I am a little confused about the arrangement for using two audio trannies. The sowter website says to ground the centre tap which is surely the bias connection. Is the problem that there is lack of clarity over the secondary and primary labelling. I suppose that a tranny designed for esl's might be labelled differently

 

[I_Forgot]

Here ya go

With two transformers, whether or not they have center taps, you wire as shown. The primaries can be connected in series or parallel, whichever works best for your transformers and ESL panels.

I_F

 

[flodge]

many thanks indeed
I have googled and found references to the concept and had worked out a possible connection in my head but the sowter web site threw me. Cheers for going to the effort of posting a schematic

Steve

 

[Pwoida]

In the lower picture posted above by I_Forgot, if an impedance of Z ohms is connected between stators A and B and each of the transformers has a turns ratio of 1:n what would the input impedance be (ie Z referred to the input) ?

 

[Calvin]

Impedance transformation

Hi,

with an ideal tranny the input impedance would be Z/n² with n depending on the connection of the primaries.
series connected primaries.....factor 1:n
parallel connected primaries...factor 1:2n
So parallel connection gives double the output voltage of series connected primaries, but the input impedance is 1/4th of it.

jauu
Calvin