Am I biasing this right?

[Tyrannocaster]

While I try to get the tremolo in this thing (basically a Tweed Pro) sorted out I am also looking at its biasing. I was afraid the B+ would be really high with this power transformer so I used 560 ohm resistors on the cathode biased 6L6s (one for each power tube) and I believe the result is that the tubes aren't running hot enough. Would someone please check my method and figures?

Measure the resistance of cathode resistor.                      560
Take a reading of the voltage (DC) at the cathode.             30
Calculate the current thru the tube...
cathode voltage divided by cathode resistance.                .054
Read the voltage at the plate.                                          398
Subtract cathode from plate voltage = net plate voltage.  368
Multiply tube current by net voltage for tube dissipation. 368 x .054 = 19.872

So if I am right and it's dissipating 20 watts, it's within acceptable operating limits but nowhere near what is possible, which should top out around 30, I think. Do I have this right?

[sluckey]

Yes, that's right.

[Tyrannocaster]

Oh, good. I did something right!  

Thanks.

EDIT: I swapped the 560s out for 510s, which is all I have on hand. I expected much more change than I got: now it's dissipating 19.2 watts, which is less than before. Hm; I thought dissipation would go up, not down. 19 watts is the design center for 6L6s so I guess I'll leave them in since I don't have anything else even close to 500 ohms on hand. Got some 180s, though. 

[phsyconoodler]

What that means is the tubes are drawingh the current that makes them happy in that particular circuit.
  I have the same thing happening in my amp with cathode biased 6L6's.
 I have a 500 ohm resistor and it wants to be there.It simply won't draw more current no matter what I end up using for a cathode resistor.And it draws the plate voltage down if I try going larger.
  I ended up leaving it be cause it absolutely sounds amazing as is.