how do you drive big power tubes like 4-250A's

[ELS122]

I've seen people use transformers to drive them, and big power tubes in cathode follower circuit.
what would be a decently simple way to drive them, preferably without another transformer.
also in a push-pull config, I intend to have a DC LTP PI driving any power tubes in cathode follower mode (if I use them and not a transformer)

[TimFox]

Transformer or cathode-follower coupling is mandatory if you run the output tubes in class AB2, where there will be substantial grid-1 current as the grid-cathode voltage goes positive.  This will cause huge problems with a coupling capacitor.
With class AB1, where there should be no grid current, you only need sufficient voltage drive into a load which is essentially capacitive.  What grid voltage swing do you need for your design?

[TimFox]

Here is the Eimac data sheet for the 4-250A.  There are two sections under "Class AB" for AB1 and AB2 operation.  Note that two of these will require 145 watts of filament power (5 V at 2 x 14.5 A).
http://tubedata.milbert.com/sheets/140/4/4-250A.pdf