Take a peek at the PI.   Nik may have sent it with a 12AX7, try a 12AT7 and see if that suits you any better.

You have to keep in mind that Ceriatione builds clones.   The schematics, for the most part and certainly in the case of a Fender VC, are all in the public domain.    There is no reason anybody should be without a schematic.
Good Luck

No, the brown and blue wires were the problem.   They are not compensating for something further back in the circuit.
As far as hum..... I would triple check all of your ground connections.   Make sure you have continuity.   Re-flow any joint that looks the least bit suspicious.   Other potential problems are your ground systems themselves.   Also, as always, lead dress can be critical.   Moving a wire 1/4' inch can make a big difference.    Again, make sure all of your ground connections are short, tight, and non-invasive as possible.   You may as well start chop sticking, see what you can improve. 
That is probably about all the help I can be for you.    You may need the service of an amp tech.   Posting some pictures may still prove to be a big help.
Good Luck

This starts to get pretty confusing (at least it does for me).   So I assume 1/2 of your phase inverter was not working.   Now that you have both halves going, you have more trouble than you did before.   You are probably going to need help from somebody better than me but, I would say you need to check your wiring again.   Verify that you have the proper volt readings everywhere.
Double check all of the "under the board" wiring and be sure that you did not miss something.   Make sure you judiciously check ALL of your work, from the input jack to the output jack.   
Bad oscillation on a newly wired amp can be caused by the OT.  You might try reversing the brown and blue wires fro you power tubes to the OT.   You will know if that was the problem or not.   It will either fix the oscillation, or make it 100 times worse.  Other than that, I do not know what to say.
Your original complaint was that your amp was too bright.   After jumping the PI cathode with one wire, you now have trouble with oscillation.   So all I can say is:
Check all of your amp against the layout, and take your time. 
You really need to check all of the important voltages throughout your amp.  I realize you do not have a schematic, maybe Nik can help you put with some expected voltages.
Flip the OT wires and see if that helps your oscillation.
Reconnect your presence.
Good Luck

Don't let me worry you about the bias stuff.  Like "wyatt" said, Ceriatone must have set the bias when they fired up your amp.  I am sure every thing is fine.    But there is a lot of wiggle room with bias.   After awhile, the numbers become almost meaningless.    Many times I have adjusted bias until the player says "OK I like it right there".  Then I check with a meter.   If the numbers don't seem stupid, to one extreme or the other, then I am done.   Does not matter if it is at 53% or 79%.   It only matters how the amp sounds to your ears and fingers.
We have amps made by Carol Ann, Roccaforte, Fargen, Two Rock, etc. etc.   I always check the bias when it gets to me.   You just never know for sure, unless you look.   And I have found a few problems doing so, but I see a lot of amps.
Enjoy your new, hand wired, Marshall master piece.   That amp will out last all of us!!!!!
Good Luck

It is certainly possible to do yourself, but it requires some knowledge and a little bit of test equipment.   If you live near me, I can do it for you.   As far as GC goes, I guess it depends on the store.   Maybe some of them employ an amp tech, I really don't know.
Good Luck

What can you say, they are great, affordable, hand wired amps.   If you bought a complete amp, make sure you check the bias after it gets to you.
Good Luck

Can you post a few pictures.   
Regards the presence, triple check your amp to the schematic.   Go real slow, physically touch the paper as you trace the path of travel.   Make sure you have made every connection, make sure all the components are correct, make sure the pot is working/passing signal, stuff like that.

This is kind of confusing.  What is the voltage at the PT secondary heater supply?   Seems like the heater wires would have to have been pretty small if they were loosing 0.50 volts.

Is the amp new?   Who put it together?

This is correct, but do you understand what he is telling you ?   Do you know what shielded cable is ?
Shielded cable has a braided "shield" that surrounds the insulation of the center conductor (wire).   That braided wire (the shield) must be pulled back and used as a ground wire.   If you look at a clean copy of your schematic, you will notice that the thin, black line you are asking about is just a ground wire.   It is connected to the input jack and the volume pot ground post.   Follow the lines and you will see that they go to the ground bus.
Good Luck

Anybody else use transformers from Magnetic Components?   Their name has popped up several times this year.

What would you say the advantage is in switching to these tubes?
Thank You

seeker -
Sounds like you are all set.  If you start to feel like it bothers you, or maybe it is getting worse, you can make a change.  You might get a lot of relief from just replacing the first filter cap after the rectifier.  Sometimes it does not take a whole lot.
Good Luck

seeker -
Your math is correct, if your assumption about a 400V plate voltage is accurate.  I have a feeling, however, that you will find it is higher than that.
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