18Watt.com

I'm planning something out of the leftover parts I've got.
First, I've got a PT from a radio which was delivering about 182mA from 250V secondary (no CT) and ~4A of 6.3V.
The OT is a somewhat beefy EL84 PP tranny.
The power tubes are 6BG6GA which are 6L6's with different pinout.
With approximately 280V B+ I want to get a nice low distortion class A 18-20W TMB guitar amp.

For preamp I wanted to use different metal envelope tubes (for aesthetic and avaliability reasons), and my inventory features a couple of 6SJ7's, 6C5's and one 6SC7.

Here's a preliminary scheme:



The questions are:
- I'm not sure about the preamp, comments welcome
- I need a bias pot (I have 2W 100ohm srewdriver pot for this) somewhere: where?
- Will the OT smoke???

Looks real cool, especially with that paraphase PI, and I would love to discuss it further. However, as it has little relationship to a Marshall 18W amp, can I ask you to repost this on our companion site PPwatt.com Your 18W username and password will work there as well.