Using two output transformers together

[jscballer]

So I have an old el84 powered stereo that uses two se output transformers one per tube, I was wondering is there was a way I could use both into one speaker or use them together somehow.

Thank you,

John

[SatelliteAmps]

You can wire them together. That's how the original Marshall 100 watt amps were done. Wire them in parallel.

[Joe F]

Adam, he would theoretically halve the ohms rating in that case, yes? (two 8ohm OTs in parallel = 4 ohms or in series = 16ohms)

I don't know if the OP is using this for stereo use or to try a guitar conversion, but though I'd mention it.

[SatelliteAmps]

Joe-You are correct. Sounds more like a mono setup to me.

[jscballer]

Ok so would i be running both transformers tied to both tubes then? If you have an example schematic of how this would work I would really appreciate it. And yes it is being used for a guitar.

Thank you,

John

[SatelliteAmps]

If you have two single ended transformers, one goes to one tube, and one goes to the other tube, and the outputs are tied together. (Think of putting the two SE transformers together to make one big P/P transformer).

If you do some research and look up the schematic for the first Marshall Super Lead, this is how it is wired up.

[donnyjaguar]

The outputs have to be wired out of phase so the + of one to the - of the other and the leftover contacts to the appropriate speaker contacts and yes, the impedance will be doubled. Another strategy is to parallel them and if you have 16Ω taps, these would be connected together driving the + of an 8Ω speaker.

There are a few different ways to do this with a tube amp.