Transformer p-s single stage Triadtron pushpull

[Circlomanen]

I have been driving to Örebro back and forth this weekend. Nothing beats being bored by endless miles of straight roads as a great opportunity to think about, develop and try out new ideas in your head.

I have been playing with the inverted "Triadtron" circuit: Aikido Cathode Follower & More Triadtron trying to simplify it. Inspired by Nelson Pass brilliant use of nice signal level transformers in simple Zen"ish" amplifiers (BAF2015 - F6 - M2 etc) I hope I can get a nice linear single stage push pull amplifier without any extra gain-devices.

In my circuit above the L1-2 L2-2 is the primary and seconday winding of the Edcor or the Jensen transformer. The secondary should be phase-reversed to the primary.

This is just a simplified schematic to show the general principle. There is no bias-circuitry in my schematic above. I would prefer depletion-mode devices (SIT) for the most simple and DC stable circuit possible, but it is doable with normal enhance mode devices too.

I have not seen this circuit used with solid state devices. Any comments or suggestions?!?
Is it worth testing?

Cheers,
Johannes

 

[Circlomanen]

A little more complete circuit. R9 and R4 should be potentiometers. I just guessed the value of those resistors. I don't know how to simulate transformers yet, so this is just a drawing at the moment.

Cheers,
Johannes

 

[Zen Mod]

from simple glance , function seems exactly same as Papa's Mu stage , ACA for example?

when lower half is opened , upper one is closing

 

[Circlomanen]

from simple glance , function seems exactly same as Papa's Mu stage , ACA for example?

It is similar, but there are also differences.

The MU-follower senses the current through the load and will react to the reactivity of the loudspeaker. The Triadtron senses the current through the resistor below the active main gain-device. The normal non transformer Triadtron seems to have more gain, less distortion and a higher damping factor then a MU-follower drain-loaded common source amplifier - all else being the same.

I have built and tested several Triadtron amps and they are quite nice.

This is just an idea I want to explore. I want more power from my single 28 volt power supply and my IRFP7430. They are real fun devices. I can not even imagine them in a powerful pushpull amplifier. I have been considering a F6 kind of circuit, and it might be much better in every way. I just like experimenting with fun ideas.

Cheers,
Johannes

 

[Nelson Pass]

I just like experimenting with fun ideas.

That's what we're here for.