5f4 build with or without screen res

[devotar]

I am looking to build a tweed super clone and was wondering what, if any, are the cons of putting in 470 ohm screen resistors. Thanks

[Alexo]

Not having built a 5F4, generally adding screen resistors increases compression and prolongs tube life.

[Firestorm]

The 5F4 already compresses like crazy because of the location of the choke. I doubt you'd even notice the screen resistors in that regard. This is one of Fender's goofy designs with the screens at higher potential than the plate (see Andy Le Blanc's recent threads for more on that subject).

I wouldn't recommend building any amp without screen resistors (unless you own a tube company). In fact in this case I'd be more comfortable with 1Ks.

[Alexo]

Wouldn't putting the choke before the plate node lessen compression?

[devotar]

Thanks for the input. would it also help then if I moved the choke after the centertap b+ on the OT. I see the other F circuits have it situated this way