How to add a balanced output to a Tube Preamp ?

[blackwhaleamp]

Hi,

I want to add a balance output on this amplifier (see attachement). The idea is to take the signal from the pre-amp and not from the output.

I was reading several threads and I found out that this transformer could do the trick

Audio-Ubertrager 1:1/2:1 fur Line-Signale LTR-110 - Tube-Town GmbH

There is a suggestion about how to connect it. But the signal is coming from the output.

Does anyone know if I could use the same transformer at the pre-amp? Like where should I connect it?

Thank for any suggestion

 

[JMFahey]

You´ll need to add a buffer Op Amp which is able to drive that transformer.
What kind of signal do you want to send it?

If post EQ and both channels available, I would suggest measuring signal at the Master Volume hot leg.
You need to attenuate such signal to 100mV RMS which is about what a direct box sends to the mixer.

 

[indianajo]

The plate of the driver triodes is push pull. They appear to be opposite in phase. You just need to attenuate the voltage swing to a proper output voltage.
Hammond did this all the time to drive their tone cabinets. They produced a roughly 7 vac signal biphase to run down the cable parallel to the 120 vac to the tone cabinet.