High gain preamp help

[dennyg]

Troubleshooting anemic fizzy tone on my Uber build. Using a listening amp while playing guitar, the tone is fine coming out of stage 1 but goes to mush sampling stage 2 grid and plate.  My gut is it's a grounding problem as I recently changed to a star ground:  3 nodes - first filter cap and pre-amp smoothing caps -  with leads bolted to chassis near the input jack.  I also rebuilt stages 1/2 in the process swapping out 4-lug with 6-lug term strips to provide a bit more space in the gothic ring layout, but did re-use the components.  I pulled second tube to rule out downstream oscillations when listening.  The DC voltages seem good (similar to when amp sounded fine) but posted for reference and consistent with load line per component values (R1 & 2 = 330K, Rk1=2.7K, Rk2=4.7K).
B+ 355v, plate 1 168v, cath 1 1.54v, plate 2 202v, cath 2 2.15
AC values (peak via scope) also seem fine with 100mv pk 440hz input signal: plate 1 4.9v, grid 2 3.0v, plate 2 120v

Any help appeciated!
Denny

[dennyg]

Attached a pic of the pre-amp circuit.  I'm convinced this is a grounding issue since first time doing a star ground and could use some advice. 
Currently using a non-isolated input jack to ground input separate from star connection to chassis - not sure if this is best method but i've seen that on other builds.  Would appreciate someone taking a look at pic and let me know if anything looks stupid, whether related to grounding or other.  This is also my first terminal strip build using gothic ring (i.e. B+ and grounds on one side, signal leads on the other - yellow wires in pic). 

[SILVERGUN]

Are you running your filaments at 12V?

[SILVERGUN]

....if not, then you have them wired incorrectly

[dennyg]

yes - 12v

[dennyg]

Well for whoever took the time to read my post, and particularly Silvergun who responded, I gave up on trying to make the true star ground work on this amp.  Reverted back to a bus star and it's happy again and hum/fizz free.  Hey, I gave it a shot.  Not sure why I couldn't get it to work but conclusion is that bus star works just fine, and if someone is inclined to implement a true star scheme then it should be part of the upfront layout design in order to minimize the leads from the nodes.  I did learn bunch of new stuff from the troubleshooting process however, which is why I try new things in the first place - and would encourage any newcomer to amp building to do the same.  And by all means build at least one  high-gainer if you really want to accelerate your learning and skills because EVERYTHING matters and tolerance to error is very low.

[PRR]

A problem with "star" is the High-Spike line from PT/Rect to first filter cap. This must not go anywhere near the "star" or contamination is likely. Generally the spikey PT/Rect should not go to "star", only the bottom of the first filter cap (and on a separate lead from the PT/Rect lead).

Star can work but at tube current levels a bus wire works good and is logical (ground follows signal).