Author Topic: Fender 2 channel Model T Tube options  (Read 2343 times)

0 Members and 1 Guest are viewing this topic.

Offline theomacy

  • Jr. Member
  • **
  • Posts: 1
Fender 2 channel Model T Tube options
« on: May 13, 2007, 02:22:08 pm »
View Post
I've got a Fender Sunn Model T on the way and I'm wondering what options I have to switch around tube types. Power tube wise it's designed for 6l6s and has jjs in it right now, but I was wondering what other kinds of power tubes I can put in it. Is it possible to put 6550s in it or kt-88s.


Additionally what experience do you all have with preamp tubes in these things. Does anyone have recommendations

Offline JoeArthur

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 729
Re: Fender 2 channel Model T Tube options
« Reply #1 on: May 14, 2007, 07:35:56 am »
6550s have almost double the heater current requirement as 6L6s - 1.6 amp vs 0.9 amp, per tube. Chances are pretty slim that the heater winding on the power transformer can provide an additional 2.8 amps. Maybe, maybe not, but I wouldn't chance it.

EL34s might be a possibility, but you'll want to check that nothing is connected to pin 1 of the output tubes and then connect it to pin 8. Then you'll have to make sure there is enough bias adjustment to properly bias them.

This amp changes the bias on the output tubes, along with the plate voltage, depending on the 25/100 watt power output switch. You'll want to make sure this bias change is appropriate for EL34s.

Much easier to keep 6L6s.

Offline SunnBurn

  • Jr. Member
  • **
  • Posts: 3
Re: Fender 2 channel Model T Tube options
« Reply #2 on: November 25, 2007, 10:50:42 pm »
I had one of these but traded it to my brother for a T50C.  We spent lots of hours experimenting with lots of different power tubes, pre-amp tubes and combinations.

Stick to 6L6s, but go with SEDs.  We experimented with Sovteks, EHs, Shuguang, SEDs, JJs, etc. and came to the conclusion that the SEDs were best.  Groove Tube 6L6GEs sounded good too, but they are pricey.

Three other suggestions: (1) use a JAN Philips or JAN GE 5751 in V1 instead of a 12AX7; (2) use a JAN Philips 12AT7 for the reverb driver; and (3) use a JAN GE 5751 for your phase inverter. 

This set up sounded excellent.  Hope our experience helps you out.