Difference in tone between JTM50 and JMP50 OT's?

[Big Mike]

I'm slowly evolving my JTM45 kit into something else. Just not a fan of several thins in that circuit.
Iv'e now got it mostly set to lead specs, split cathode, .0068 V1B, EL34's,. yadda yadda.

So I'm thinking maybe I should swap out the OT for something more in line with what it's morphing to?

So all things being considered, in a Stock metro PT'd amp with the above changes, what's the difference between a 79-128 and a 79-139 OT's going to be?

Also should I be looking at a different choke?

Thanks
Mike

[OnTheFritz]

The 784-128 has a 3.5K primary, like the 139', but also has a buried 100V tap which apparently does affect the tone.

Here's Marstran's 128 OT. Two in stock!

http://www.marstran.com/50W%20OT%20128.htm" onclick="window.open(this.href);return false;

[Big Mike]

Yeah but what's the sound difference?

[Big Mike]

Duh of course I meant 784-128 and 784-139

Brain fade...